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How to Self-Diagnose Nutritional Disorders

Can you live into your sixties and seventies without taking basic vitamins? Absolutely, many people do. Will you have a quality of life worth living? Absolutely not, because nutritional disorders from vitamin deficiencies and the drugs prescribed to treat them are the primary causes of age-related dementia, heart disease, strokes, cancers, and countless other equally debilitating conditions.

Adding insult to injury, all of these conditions are easily avoidable and preventable with a daily dose of a quality multivitamin supplement costing less than 50 cents a day. Instead, most adults are hooked on multiple medications, which only exacerbate their decline. As of 2025, Americans spend $1,635 per capita on prescription drugs.

‘Per capita’ means every single living person, including all infants, toddlers, preteens, teens, and young adults. Most people over 50 are spending many times more than younger adults because they use multiple medications for chronic diseases such as hypertension, diabetes, heart disease, heartburn, enlarged prostate, thyroid disease, osteoporosis, chronic pain, constipation, and numerous others.

You may already have some of these conditions even if you are taking consumer-grade supplements, such as One-A-Day or Centrum, because of the subpar quality and quantity of their ingredients.

The following summary outlines primary conditions related to vitamin deficiencies and notable symptoms or side effects. Some of the conditions may be connected to more than one vitamin:

Vitamin A Deficiency

Vitamin A, also known as retinol, is a fat-soluble vitamin essential for vision, immune function, cellular growth, reproduction, and the maintenance of skin, mucous membranes, and other tissues. It exists as preformed vitamin A (retinol and retinyl esters) in dairy products, liver, and fish, and as beta-carotene in bright orange fruits and vegetables such as mangoes and carrots.

Vitamin A plays a critical role in forming the pigments required for night and color vision, supports healthy growth and remodeling of cells throughout the body, helps maintain strong defenses against infection, and is vital for normal fetal development.

Vitamin A deficiency can result in impaired vision (including night blindness), increased infection risk, skin and mucous membrane disorders, growth retardation in children, and increased vulnerability to severe illnesses. Regular intake is necessary, but excessive supplementation can lead to toxicity, affecting the liver, bones, and nervous system. Below are the primary systemic disorders and their clinical manifestations:

Eye Disorders

Skin Disorders

Immune System Disorders

Growth and Development Disorders

Reproductive and Other System Effects

When I was a child growing up in the 1950s and 1960s in post-World War II Ukraine, my mother had a daily ritual of having me drink half a glass of carrot juice – an abundant source of beta-carotene. Why juice, not carrots? To avoid the fiber.

Vitamin D Deficiency

Vitamin D refers to a family of fat-soluble compounds that play a central role in regulating the body’s absorption of calcium, magnesium, and phosphate, among other physiological processes. In humans, the two primary forms are vitamin D3 (cholecalciferol) and vitamin D2 (ergocalciferol), both of which contribute to maintaining mineral balance and supporting various metabolic functions.

Naturally found in oily fish, egg yolks, fortified milk, and some mushrooms, vitamin D is critical for preventing rickets in children and osteomalacia or osteoporosis in adults. Beyond bone and mineral health, emerging evidence points to roles in immune modulation and potential effects on cardiovascular and metabolic health.

Vitamon D deficiency is widespread in populations with limited sun exposure, darker skin, advanced age, and poor dietary intake, leading to increased risks for bone deformities, fractures, muscle weakness, and potentially higher susceptibility to infections and chronic diseases.

Skeletal System

Rickets, idiopathic scoliosis, and osteomalacia are, in my view, variations of the same underlying condition — bone softening from vitamin D deficiency, mineral deficiency, or both. The only real differences are the patient’s age and the anatomical impact based on the stage of skeletal development. When I raise this point with doctors, it is often dismissed, even by osteopathic physicians who should know better, simply because it isn't documented in their textbooks.

This pattern — the assumption that if something hasn’t been taught in medical school, it doesn’t exist — is typical of individuals with a so-called fixed intelligence mindset. That mindset is more common in hierarchical, high-stakes fields such as law, finance, and medicine, where memory and conformity are commonly mistaken for competence.

This problem is broadly recognized in progressive medical schools, which now place greater emphasis on adaptive thinking, curiosity, and empathy to counter the dark side of rote learning and rigid frameworks.

The fixed mindset is especially entrenched in cultures where hierarchy, rote memorization, and deference to 'authority' override independent thinking. A well-known example comes from aviation: Korean Air, after a series of fatal crashes, hired European pilots to break down the deeply ingrained cultural norms that discouraged second officers from questioning their superiors. The parallels to medicine are hard to ignore.

In contrast, growth mindsets and fluid intelligence are more common in environments that reward curiosity and adaptability. You can probably guess which mindset occupies my head.

Muscular System

Neurological and Neuromuscular Disorders

Immune System

Metabolic and Systemic Manifestations

Dental/Periodontal disorders

The vitamin D deficiency epidemic in the United States is exacerbated by fear-mongering about sun exposure, low-fat diets, and widespread use of cholesterol-lowering drugs. Here is what connects these three factors.

These three forces together created a perfect “shit-storm” for vitamin D deficiency epidemics among Americans of all ages. I am one of the very few people who have been writing and talking about it since the early 2000s, but my megaphone is too small to move a needle.

If you belong to the no sun, no fat, no cholesterol, and no salt cult, at the very least, take a quality multivitamin to prevent the damage I described above.

I mentioned table salt here because it is the primary source of two critical electrolytes — sodium and chloride, and, indirectly, a microelement iodine, that we’ll discuss later in this cycle.

My late mother was a card-carrying member of that cult. Lo and behold, she suffered from chronic constipation for most of her life, lost all her teeth in her fifties, and developed bowed legs in her sixties.

Ultimately, the combined beliefs and practices espoused by my mother and people like her created the perfect conditions for widespread vitamin D deficiency hidden in public dietary advice, overlooked in clinical practice, and dismissed until the damage is done. Don’t be an unwitting dupe.

Vitamin E Deficiency

Vitamin E refers to a family of fat-soluble compounds, primarily including four tocopherols—alpha-, beta-, gamma-, and delta-tocopherol—and four corresponding tocotrienols. It is found abundantly in nuts, seeds, plant oils, green leafy vegetables, and fortified foods.

Vitamin E is essential for immune function, skin and eye health, and maintaining the structural integrity of blood vessels. It also supports cellular processes by regulating gene functions and modulating enzymatic activity. The body stores vitamin E mainly in adipose tissue and the liver.

Its deficiency can lead to serious neurological, muscular, blood, vision, and immune disturbances, particularly in individuals with fat malabsorption issues. The body stores vitamin E in fatty tissues and the liver, reflecting its vital role in health and longevity.

Neurological disorders

The last two symptoms are reminiscent of former President Biden’s appearance and performance during his last debate with Donald Trump, most notably difficulty with balance and coordination, an unsteady gait, and slurred, slow speech. No one is immune to vitamin E deficiency, not even the presidents of the United States.

Muscular System

Blood Disorders

Eye Disorders

Immune System

Erectile Dysfunction (ED)

Vitamin K Deficiency

Vitamin K is a group of fat-soluble compounds, primarily vitamin K₁ (phylloquinone) and a series of vitamin K₂ forms (menaquinones, which are critical for blood coagulation, bone metabolism, and calcium balance regulation.

Vitamin K₁ is found predominantly in green leafy vegetables and plant oils, while K₂ is present in fermented foods, meats, cheeses, and egg yolks. The body absorbs vitamin K with dietary fats and stores it in the liver and fatty tissues.

In addition to dietary sources, a portion of vitamin K (particularly K₂) is synthesized by bacteria in the large intestine. However, this contribution varies widely depending on the composition of the microbiome and is generally insufficient on its own to meet the body’s full requirements, especially in infants, individuals taking antibiotics, anyone using PEG-based laxatives (such as Miralax) with antibacterial effects, and anyone with gut dysbiosis.

Beyond its classic role in blood clotting and bone health, emerging evidence highlights vitamin K’s importance for cardiovascular, metabolic, and cognitive functions as well.

Vitamin K deficiency leads to several distinct clinical syndromes, chiefly due to impaired activation of vitamin K-dependent proteins in blood, bone, and other tissues.

Blood Disorders

Bone and Musculoskeletal Disorders

Vascular and Soft Tissue Disorders

Other Clinical Manifestations

In summary, vitamin K is indispensable for the synthesis of proteins involved in blood clotting, bone integrity, and vascular health. At-risk populations can experience severe, potentially life-threatening bleeding and long-term impacts on bone, heart, and brain health. Recognition of at-risk groups and consistent intake of vitamin K supplements is essential for health and longevity.

Vitamin C Deficiency

Vitamin C (ascorbic acid) is a water-soluble vitamin essential for human health. It is necessary for the synthesis of collagen, a key structural protein in connective tissues, skin, bones, and blood vessels. Vitamin C also enhances iron absorption from the digestive tract, supports immune defense, and aids in neurotransmitter production.

The body cannot synthesize or store vitamin C in any amounts, making regular dietary intake vital. Deficiency can have profound systemic effects and, in severe cases, lead to scurvy, a condition historically associated with sailors and others deprived of fresh produce.

I experienced an early stage of scurvy in my early twenties when, as a student on summer break, I was sent to a compulsory labor camp to build a manure pit and lay cement on the roof of a massive barn. While there, we ate almost exclusively pork, butter, eggs, bacon, wheat cereals, and macaroni—without a single serving of fruits or vegetables.

After about 20 days on this regimen, my gums started bleeding, facial hair stopped growing, and my toenails became so soft I could tear them away. Fortunately, the "exile" ended after 30 days, and once I returned home, things gradually returned to normal. But the experience left a lasting impression. Had we stayed even a month longer, the outcome could have been much worse.

Vitamin C is found in fresh fruits such as citrus, berries, and kiwi, and vegetables such as peppers, tomatoes, and leafy greens. Unfortunately, vitamin C begins to deteriorate in fruits and vegetables immediately after harvest, with substantial losses occurring within days.

Refrigeration slows the loss but does not prevent it, while room temperature and processing significantly accelerate the decline. After 15 days at room temperature, vitamin C loss can approach 100% in most fruits and vegetables, and ranges from 50% to 90% even with refrigeration.

The average time between harvest and supermarket purchase is about 2 to 14 days for most “fresh” produce, but can extend to several months for long-storage items like apples and carrots. In other words, the idea that you can meet your vitamin C needs from “fresh fruits and vegetables” is a pipe dream.

For the same reason, orange juice is fortified with synthetic vitamin C. Unfortunately, in addition to a meager amount of vitamin C, each glass (8 oz) of bottled orange juice contains, on average, around 23 grams of sugar—almost exactly a tablespoon and a half.

So if you’re wondering why your child or grandchild can’t sit still, can’t fall asleep, can’t concentrate, and can’t hold their urine while asleep, it often starts with that glass of orange juice.

Vitamin C deficiency manifests in a range of disorders related to its critical role in collagen synthesis and immune function. Symptoms often develop gradually and can be subtle before progressing to more serious conditions.

Blood and Vascular Disorders

Connective Tissue and Musculoskeletal Disorders

Dermatologic Disorders

Immune System Disorders

Neuropsychiatric Disorders

Scurvy

In summary, vitamin C is indispensable for connective tissue integrity, vascular and immune health, and psychological well-being. Deficiency presents as a spectrum, from fatigue and easy bruising to the severe, multi-systemic disorder of scurvy.

Consuming a diet rich in fruits and vegetables offers, at best, marginal protection against this preventable condition, and, for many children and adults, becomes a near-certain path to obesity and diabetes because of excessive intake of plant sugars.

Vitamin B1 Deficiency

Vitamin B1, also known as thiamine, is a water-soluble vitamin vital for energy metabolism and normal nerve, muscle, and heart function. It acts as an essential coenzyme in carbohydrate metabolism, enabling the body to convert glucose into energy, and is critically involved in the functioning of the nervous system.

Thiamine is found naturally in whole grains, legumes, nuts, seeds, pork, and fortified cereals. Because it is not stored in significant amounts and is easily lost during food processing and cooking, consistent dietary intake is crucial.

Thiamine deficiency can develop quickly in situations of poor nutrition, chronic illness, alcoholism, or increased metabolic needs and leads to distinct, serious clinical syndromes affecting the nervous and cardiovascular systems.

Neurological Disorders

Cardiovascular Disorders

Musculoskeletal and General Symptoms

Gastrointestinal Symptoms

In summary, vitamin B1 is indispensable for energy metabolism and nervous system health. Deficiency presents swiftly with potentially life-threatening neurologic and cardiovascular signs, but is rapidly reversible with prompt treatment if caught early. Vulnerable populations benefit most from awareness, prevention, and attention to adequate, consistent intake of B-complex supplements that contain thiamine.

Vitamin B2 Deficiency

Vitamin B2, or riboflavin, is a water-soluble B vitamin essential for human health. It acts as a fundamental coenzyme in energy metabolism, enabling the body to convert carbohydrates, fats, and proteins into usable energy.

Riboflavin is found naturally in dairy products, eggs, lean meats, green leafy vegetables, nuts, and whole grains, and it must be replenished daily due to minimal body storage. It plays critical roles in cellular growth, tissue repair, red blood cell production, and the maintenance of healthy skin, mucous membranes, eyes, and nervous system.

Riboflavin deficiency (ariboflavinosis) most often affects tissues with rapid cell turnover and high energy demand, resulting in a range of clinical features that reflect the vitamin’s diverse metabolic functions.

Skin, mouth, and mucous membrane symptoms

Eye Disorders

Blood Disorders

Neurologic and Developmental Disorders

Other Health Impacts

In summary, vitamin B2 is indispensable for energy production, cellular growth and repair, and maintaining healthy skin, eyes, and nervous tissue. Deficiency primarily affects rapidly growing or metabolically active tissues, producing characteristic oral and skin symptoms, most notably cracks at the mouth corners, swollen tongue, and light sensitivity. Early detection and repletion are key, as supplementation quickly reverses symptoms and prevents complications, underscoring the essential nature of riboflavin to systemic health.

Vitamin B3 Deficiency

Vitamin B3, also known as niacin, is a water-soluble B vitamin crucial for converting macronutients into energy and supporting the health of the skin, digestive tract, and nervous system. Niacin exists in two principal forms—nicotinic acid and niacinamide (nicotinamide). Both are present in meat, fish, nuts, whole grains, legumes, and fortified cereals.

The body can also synthesize some niacin from the amino acid tryptophan. Because it cannot be stored in large quantities, a steady dietary supply is needed. Niacin is a key component of the coenzymes NAD and NADP, essential for hundreds of biochemical reactions, including energy production and DNA repair.

Deficiency of niacin can result in a spectrum of systemic disorders collectively termed pellagra that affect organs with high metabolic demand and cells turnover.

Neurological Disorders

Dermatological Manifestations

Gastrointestinal Disorders

All three conditions are commonplace among people taking GLP-1 drugs for weight loss, whose diets are notoriously deficient in all essential vitamins and minerals.

Musculoskeletal and General Disorders

Blood Disorders

Other Health Impacts

Pellagra

In summary, vitamin B3 is essential for energy metabolism, DNA repair, and skin, nervous system, and digestive tract health. Timely recognition and replenishment of niacin are critical, as its deficiency symptoms can progress from mild and reversible to severe and life-threatening.

Vitamin B5 Deficiency

Vitamin B5, also known as pantothenic acid, is a water-soluble B vitamin found in nearly all animal and plant-based foods, reflecting its name from the Greek “pantos,” meaning “everywhere.” Vital for health, it acts as a coenzyme in energy metabolism, helping convert carbohydrates, fats, and proteins from food into usable energy.

Pantothenic acid is especially important for the synthesis of coenzyme A (CoA), which is involved in fatty acid metabolism, red blood cell formation, hormone synthesis (including sex and stress hormones), and the maintenance of healthy skin, hair, eyes, liver, and nervous system. Because of its widespread presence in food, deficiency is rare in healthy populations, but more likely in severe malnutrition or certain genetic conditions.

Deficiency in pantothenic acid primarily affects functions and tissues that depend most heavily on rapid energy production and fatty acid metabolism.

Neurological and Musculoskeletal Disorders

Systemic and General Disorders

Gastrointestinal Disorders

Blood Disorders

Skin, Hair, and Mucous Membranes

Special Clinical Syndromes

In summary, vitamin B5 (pantothenic acid) is essential for energy production, fatty acid metabolism, red blood cell formation, hormone synthesis, and the health of skin and nerves. Its deficiency can lead to a combination of neurological disturbances such as burning feet, numbness, and muscle cramps, fatigue, sleep issues, digestive discomfort, and problems with skin or hair, though these symptoms are uncommon outside of severe malnutrition or rare genetic disease.

Vitamin B6 Deficiency

Vitamin B6, or pyridoxine, is a water-soluble B vitamin that is crucial for normal brain development, the maintenance of healthy nervous and immune systems, and the metabolism of proteins, fats, and carbohydrates. It acts as a coenzyme in over 100 essential enzymatic reactions. Vitamin B6 is found in poultry, fish, organ meats, potatoes, bananas, chickpeas, nuts, and fortified grains. Because it is not produced in the body and only small amounts are stored, daily intake from the diet or supplements is necessary.

Vitamin B6 deficiency occurs in individuals with poor nutrition, chronic alcoholism, certain medications, or malabsorption, and results in a large number of systemic disorders.

Neurological Disorders

Blood Disorders

Dermatitis and Mucous Membrane Disorders

Immune System Disorders

Other Systemic Effects

In summary, vitamin B6 (pyridoxine) is a fundamental nutrient for energy metabolism, neurotransmitter synthesis, immune defense, hemoglobin production, and the health of nerves, skin, and mucous membranes. Deficiency can cause peripheral neuropathy, seizures, mood and cognitive disturbances, anemia, dermatitis, and impaired immunity. Because vitamin B6 is widely available in foods but easily depleted, ensuring consistent intake from food and supplements is critical for systemic health and disease prevention.

Vitamon B7 Deficiency

Vitamin B7, commonly known as biotin, is a water-soluble B vitamin critical for human health. Acting as a coenzyme in numerous metabolic pathways, biotin is essential for converting carbohydrates, fats, and proteins into usable energy. It is vital for the synthesis of fatty acids, amino acids, and glucose (via gluconeogenesis), and plays a role in maintaining skin, hair, and nail health. 

Biotin also supports normal nervous system function, gene regulation, and cell growth. As the body cannot store or synthesize significant biotin, regular dietary intake from sources like eggs, nuts, seeds, meat, fish, and some vegetables is required. Deficiency is rare but can occur in cases of malnutrition, certain genetic disorders, or prolonged use of specific medications.

Although uncommon, biotin deficiency can have significant consequences, especially in rapidly dividing or high-demand tissues.

Dermatological and Hair Disorders

Neurological and Developmental Disorders

Metabolic and General Disorders

Special Conditions

In summary, vitamin B7 (biotin) is indispensable as a coenzyme for metabolic reactions that release energy from food and ensure healthy skin, hair, and nerve function. Deficiency—though rare—can result in dermatitis, alopecia, neurological disruption (such as seizures, ataxia, and developmental delay), and general fatigue. Early recognition and prompt supplementation lead to rapid reversal of symptoms, reaffirming the critical systemic roles biotin serves throughout life.

Folate Deficiency

Folate, also known as vitamin B9, is a water-soluble B vitamin essential for numerous metabolic functions. In its natural form, it is found in foods, while the synthetic version used in supplements and fortified products is called folic acid. 

Folate acts as a coenzyme in the synthesis of DNA and RNA, supports the production of red and white blood cells in the bone marrow, and plays a key role in amino acid metabolism. It is especially critical during periods of rapid cell growth and division, such as pregnancy and infancy.

Folate is abundant in leafy green vegetables, legumes, citrus fruits, and whole grains, while folic acid is used to fortify foods because of its stability during processing. Adequate daily intake is necessary because folate is not stored in large amounts and is sensitive to cooking and processing losses. Deficiency is relatively common in certain populations due to absorption problems, dietary insufficiency, or increased physiological demand.

Deficiency of folate can cause diverse and significant health problems, especially in tissues with high rates of cell turnover and in physiological conditions requiring rapid cell division.

Blood Disorders

Neurological and Developmental Disorders

Gastrointestinal and Mucocutaneous Disorders

Pregnancy-Related Disorders

Cardiovascular and Metabolic Disorders

In summary, vitamin B9 (folate) is indispensable for DNA and RNA synthesis, red blood cell formation, and normal growth, especially in early development and pregnancy. Deficiency can cause megaloblastic anemia, oral and mucocutaneous lesions, neuropsychiatric disturbances, and—most critically—potentially irreversible birth defects and developmental delays in infants. Maintaining adequate folate intake from a variety of food sources or supplements, where necessary, is vital for health throughout all life stages.

Vitamin B12 Deficiency

Vitamin B12, or cobalamin, is a water-soluble B vitamin essential for the health of the nervous system, DNA synthesis, and the formation of red blood cells. It acts as a coenzyme in key metabolic reactions, particularly in the conversion of homocysteine to methionine and in the metabolism of fatty acids and amino acids.

Vitamin B12 is found naturally in animal products such as meat, fish, dairy, and eggs; only trace amounts are present in plant foods unless fortified. The vitamin is unique among B vitamins in that it is stored in the liver in significant amounts, allowing the body to meet its needs for months or even years.

Because B12 absorption relies on specialized proteins (intrinsic factor) and adequate stomach acidity, deficiencies may develop from malabsorption, certain medical conditions, and strict vegan diets.

B12 deficiency produces a spectrum of potentially serious disorders that primarily impact rapidly dividing cells (such as those in the blood and gastrointestinal tract) and the nervous system.

Blood Disorders

Neurologic and Psychiatric Disorders

Gastrointestinal and General Disorders

Reproductive and Developmental Disorders

In summary, vitamin B12 (cobalamin) is fundamental for healthy blood, nerves, and DNA synthesis. Deficiency leads to characteristic megaloblastic anemia and a range of neurological and neuropsychiatric disorders, some potentially irreversible if not treated, along with fatigue, mucosal changes, and, in severe cases, serious complications in infants or during pregnancy. Ensuring regular intake from animal foods or supplements is critical for those at risk.

Frequently Asked Questions

Q. Can I really get all the vitamins I need from a balanced diet?+

In theory, a balanced diet should provide all the essential nutrients your body needs. In practice, that claim is a fraud—unless you count government-mandated fortification of milk with vitamin D, orange juice with vitamin C and calcium, wheat flour with folic acid, iron, and B vitamins (thiamin, riboflavin, niacin), and white rice with similar B-complex vitamins. 

The problem is, these fortifications use minimal doses just enough to prevent overt deficiency diseases in population-wide surveys, not to sustain optimal health. The synthetic forms used are often poorly absorbed or less bioavailable than those found in high-quality supplements or real food. And since these additions are designed for mass stability, not potency, they do little to replenish depleted tissue stores or support long-term wellness.

To meet even the minimal daily requirements from fortified foods alone, you’d have to consume impractically large quantities, such as 4 cups of low-fat milk for vitamin D, 2 glasses of orange juice for vitamin C and calcium, multiple servings of white bread or breakfast cereals for folic acid and iron, and several cups of white rice for B vitamins. 

The nutritional cost of this approach is steep: undesirable lactose from milk, excessive sugar from juice, and loads of carbohydrates from cereals, bread, pasta, and rice. This pattern drives weight gain and prediabetes while still failing to deliver optimal micronutrient status.

Even if you eat organic, agricultural practices have depleted the mineral content of soils, processed foods dominate the modern diet, and long storage and shipping times degrade fragile vitamins like C, B1, B2, and folate.

And most people fall short when it comes to fat-soluble vitamins A, D, E, K because a low-fat, carbs-heavy diet doesn't provide these vitamins at all.

For older adults, digestive efficiency declines with age, further limiting nutrient absorption even when intake is adequate. Medications for blood pressure, cholesterol, diabetes, and acid reflux can interfere with the absorption or metabolism of key nutrients. This is why clinical nutrition surveys consistently show widespread deficiencies or borderline insufficiencies in the general population, even among those who believe they eat well.

Q. What are the early signs of vitamin deficiencies I should look for?+

Vitamin and mineral deficiencies don't always produce obvious or dramatic symptoms at first. Instead, they tend to manifest as vague, persistent problems that are commonly attributed to stress, aging, or poor sleep.

Fatigue, irritability, brittle nails, hair thinning, dry or flaky skin, poor concentration, and mood disturbances can all signal micronutrient deficits. Frequent infections, delayed wound healing, easy bruising, and persistent muscle cramps are other red flags.

Because these symptoms overlap with many common conditions, they often go unrecognized until a deficiency becomes severe. For example, chronic low B12 may cause fatigue and numbness for years before evolving into irreversible nerve damage.

Likewise, low vitamin D levels can quietly erode bone density long before osteoporosis shows up on a scan or a fracture occurs. Paying attention to persistent, unexplained changes in how you feel can offer early clues.

Q. How long does it take to feel better after starting supplements?+

The response to supplementation varies depending on the type and severity of deficiency. Water-soluble vitamins like B12, folate, or vitamin C may produce noticeable improvements within weeks, particularly in energy, mood, and immunity. For fat-soluble vitamins A, D, E, and K, or when dealing with chronic conditions, the effects may take several months to become noticeable, especially if tissue repair or metabolic improvements are involved.

It may take six months to a year for full benefits to emerge, especially in older adults or anyone recovering from long-standing deficiency. This delay is caused by the time needed for cellular turnover, tissue remodeling, and the gradual repletion of vitamin stores.

Consistency and quality of supplements and their absorption also matter. If, for example, you have long-standing gastritis or enteritis, even the best supplements wouldn't be able to be assimilated partially or at all, regardless of their quality.

Q. Do I really need supplements if I'm not visibly sick?+

If I say "yes," you would suspect my motivation because we sell supplements on this site. If I say "no," you'll question my sanity. The best I can say is this: visit a nursing home and observe its residents, especially the younger ones. If you don't want to become like them, the answer is yes, you should. If you don't care, then don't take supplements, don't wear seat belts, ignore the speed limit, and enjoy your life to the fullest.

On a more serious note, many vitamin and mineral deficiencies operate below the threshold of immediate illness, creating what is known as a subclinical deficiency. Over time, 'subclinical' becomes 'clinical,' and so are the risks for cardiovascular disease, osteoporosis, cognitive decline, immune dysfunction, and all other perils I described above.

To summarize, much like brushing teeth or exercising, supplementation is a preventive habit. If you are past 50, it becomes even more important because nutrient absorption declines while the demands of the aging body increase. So, if you don't want to spend your 'golden years' in the nursing home, yes, you should start taking supplements while still healthy.

Q. Isn't there a risk of overdosing on vitamins?+

Yes, there is. Water-soluble vitamins such as B-complex and C are usually excreted in the urine if taken in excess. Fat-soluble vitamins A, D, E, and K, however, are stored in the body and can accumulate if megadosed over long periods. The risk of toxicity typically arises from taking ultra-high doses without medical supervision, often over months or years.

Reputable multivitamins are formulated with safety margins in mind and rarely contain dangerous amounts of any single nutrient. Problems usually occur when people take multiple high-potency products simultaneously, like stacking a multivitamin with high-dose individual supplements, without accounting for overlap. When in doubt, consult a qualified practitioner and stick to supplements with transparent labeling and from the vendor you trust.

Q. What's the difference between water-soluble and fat-soluble vitamins?+

Water-soluble vitamins, such as vitamin C and the B-complex group, dissolve in water and are not stored in large quantities in the body. This means they must be replenished regularly through diet or supplements. Excess amounts are typically excreted in urine, which is why consistent daily intake is more important than taking high doses occasionally. These vitamins support energy production, red blood cell formation, immune defense, and nervous system function.

Fat-soluble vitamins A, D, E, and K, by contrast, are absorbed along with dietary fat and stored in the liver and fat tissues. Because the body can retain them for longer periods, deficiencies may take longer to develop—but so can toxicities if taken in very high doses over time. These vitamins are crucial for functions like vision, hormone regulation, bone metabolism, antioxidant protection, and blood clotting. Their absorption is impaired by low-fat diets, fat malabsorption conditions, or use of fat-blocking medications.

Q. What role do medications play in vitamin and mineral deficiencies?+

Many commonly prescribed medications interfere with the absorption, metabolism, or excretion of essential nutrients. For example, proton pump inhibitors (PPIs) and antacids reduce stomach acid, which is necessary for absorbing B12, iron, calcium, and magnesium. Diuretics used for blood pressure and heart conditions can deplete potassium, magnesium, and thiamine. Metformin, widely prescribed for type 2 diabetes, is associated with B12 deficiency over time.

Long-term use of antibiotics disrupts gut flora that help synthesize vitamins such as K2 and certain B vitamins. Cholesterol-lowering statins may reduce levels of CoQ10, a compound vital for energy production in cells. Even over-the-counter drugs like laxatives or aspirin can affect nutrient absorption or increase nutrient loss. Patients on chronic medication regimens should monitor their nutritional status proactively, especially as they age or add additional prescriptions.

Q. Why are older adults more vulnerable to deficiencies?+

As we age, several physiological changes make it harder to maintain adequate nutrient levels. Stomach acid production declines, reducing the absorption of key nutrients like B12, calcium, iron, and magnesium. Kidney and liver function may also decline, impairing nutrient conversion and storage. Appetite tends to decrease with age, and many older adults consume less food overall, which naturally limits nutrient intake.

Compounding this is the high prevalence of chronic disease and medication use in older populations, both of which further interfere with nutrient balance. Additionally, mobility issues or dental problems can limit access to fresh, nutrient-rich foods. This makes targeted supplementation not just helpful, but necessary to preserve muscle mass, cognitive function, bone strength, and immunity in later life.

Q. What is the difference between deficiency, insufficiency, and subclinical deficiency?+

A deficiency is a severe lack of a nutrient that leads to clearly diagnosable disease like, for example, scurvy from a lack of vitamin C or rickets from a lack of vitamin D. These conditions are often accompanied by unmistakable symptoms and confirmed through blood tests or clinical signs. They are relatively rare today but still occur, especially in at-risk populations.

Insufficiency or subclinical deficiency refers to marginally low levels that may not produce immediate symptoms but still impair physiological function over time. This is far more common. People with insufficient vitamin D, for instance, may not have bone pain or fractures yet but may experience fatigue, poor immune response, or mood disturbances. Subclinical deficiencies are often overlooked in clinical practice, even though they can have serious long-term effects if left unaddressed.

Q. How do I choose a high-quality supplement?+

Look for brands that conduct third-party testing for purity, potency, and contaminants. Reputable manufacturers will disclose this on their website or product packaging. Avoid supplements with artificial colors, fillers, or unnecessary additives. Transparent labeling and clear dosage information are good indicators of quality.

Also consider the form of the nutrient. Some vitamins and minerals have better bioavailability than others. For example, methylcobalamin is a more absorbable form of B12 than cyanocobalamin; magnesium glycinate is gentler and more effective than magnesium oxide. Cost is not always a reliable indicator, but very cheap products often cut corners on sourcing, formulation, or testing. If you're investing in your health, make sure you're getting what you're paying for.

Q. What is the difference between Recommended Dietary Allowance and Optimal Daily Allowance?+

The Recommended Dietary Allowance (RDA) is the minimum daily intake level set by the United States Department of Agriculature (USDA) to prevent overt deficiency diseases in healthy individuals. It’s a population-wide baseline, not a personalized target. For example, the RDA for vitamin C is just 90 mg per day — enough to prevent scurvy, but not necessarily enough to support optimal immune function or tissue repair.

In contrast, the Optimal Daily Allowance (ODA) refers to nutrient levels aimed at achieving peak physiological performance, disease prevention, and long-term health. These values are based on clinical research, practitioner experience, and emerging science rather than just deficiency prevention. For many nutrients, the ODA may be many times higher than the RDA. Most professional-grade supplements are formulated closer to ODA levels for these reasons.

Our supplements are formulated according to ODA rather than minimal RDAs. If you're taking supplements to stay well rather than just avoid getting sick, ODA-based formulas offer a more practical and effective approach.

Q. Why do you recommend taking coenzymated vitamins? What does it mean?+

Coenzymated vitamins are the active, body-ready forms of nutrients—essentially the versions your cells can use without any additional conversion steps. Many standard vitamins (like folic acid or cyanocobalamin) are inactive precursors that must first be converted by the liver or other tissues into their biologically active forms (like methylfolate or methylcobalamin) before your body can benefit from them.

This conversion process can be inefficient, especially in older adults or those with common genetic mutations that impair activation. By taking coenzymated vitamins, you're bypassing these bottlenecks and delivering nutrients in the exact form your body needs. This improves absorption, speeds up results, and minimizes waste. It also reduces the risk of unmetabolized compounds lingering in the body, which is a concern with synthetic precursors like folic acid.

Making matters worse, up to 70% of the population carry genetic mutations, such as variations in the MTHFR or MTRR genes, that reduce the body's ability to convert standard vitamin forms into their active counterparts. For example, people with MTHFR mutations may have difficulty converting folic acid into methylfolate, the form required for critical processes like DNA repair and neurotransmitter synthesis.

For more details, see MTHFR Genetic Testing: Controversy and Clinical Implications, a comprehensive review published in the Australian Family Physician journal that outlines the prevalence, significance, and clinical relevance of MTHFR polymorphisms.

This means that even if you take a conventional supplement, you might not benefit from it unless it contains the coenzymated (active) version of the nutrient. By using only coenzymated vitamins, we help bypass these limitations and ensure that our supplements are effective for the widest range of people, regardless of their genetic makeup.

For all of the above reasons, our multivitamin formula is made with coenzymated B-vitamins that are utmost critical for individuals with genetic mutations, increased nutritional needs or compromised metabolism.

Q. How long should I take vitamins for?+

Vitamins are not drugs. They are essential micronutrients that your body cannot produce and that you cannot reliably get from food alone. For that reason, you should take basic vitamins for as long as you plan to live.

Can you take breaks? Sure! Can you miss a day or a week? Sure! Can you miss a month? Sure! Can you miss a year? Sure! But after a few months, make sure to come back to reread this page.

Q. Do medical doctors take vitamins?+

Yes, according to surveys, over 75% of them do because doctors know a great deal more about vitamin deficiencies and related disorders than their patients and because these two subjects are an essential part of their training, licensure, and continuous medical education that is mandatory in the United States.

Most practicing physicians generally see about 20 patients per day, work around 220 days per year, and have a career spanning from 30 to 40 years. Seeing that many patients day in, day out, month after month, year after year, they come across every conceivable human frailty and an immense variety of nutritional disorders ranging from subtle deficiencies to severe malnutrition.

With all that knowledge and clinical experience, even the most skeptical doctors must occasionally wonder: If my 'healthy diet' is truly adequate, then why are so many of my patients on a similar diet so sick?   This nagging question becomes harder to dismiss after noticing the same patterns over and over again.

And they have a lot to lose by getting sick. The full cost of a U.S. medical education, including living expenses and fees, is between $250,000 and $400,000 for four years, depending on school type and location.

In return, a medical doctor in the United States can expect average lifetime earnings of around $7 to $8 million for primary care physicians on the low end, and $10 to $12 million for specialists on the high end.

Since being a doctor is incredibly taxing physically, mentally, and emotionally, no responsible physician would want to squander their hard-earned career on the most basic nutritional disorders that can be so easily prevented with a capsule or two of the most basic vitamins. And that's what most of them do!

Takeaways

If you're currently dealing with any of the conditions described above, or if you have a family history of chronic diseases like heart disease, diabetes, cognitive decline, or osteoporosis, there’s a strong likelihood that nutritional deficiencies are part of the picture. Fortunately, you don’t need a prescription to act. Here’s what you can do today to prevent and reverse these conditions.

1. Start with a professional-grade multivitamin. Skip the supermarket brands. Most consumer supplements are underdosed, poorly absorbed, or made from inferior ingredients. A well-formulated multivitamin should provide balanced, bioavailable forms of essential nutrients, especially the fat-soluble vitamins (A, D, E, and K), key B-complex vitamins, magnesium, zinc, selenium, and iodine. To learn more about professional-grade supplements, please check the How Do the Rich and Famous Get Their Supplements? article.

2. Review your symptoms against deficiency patterns. Many early signs of deficiency are vague: fatigue, irritability, poor sleep, frequent infections, slow healing, or mental fog. Use the cheat sheets included in this article to identify likely gaps based on your symptoms, history, or current medications.

3. Adjust your diet and habits, but don’t rely on food alone. Food quality today isn’t what it was 50 years ago. Nutrient losses from soil depletion, food storage, and cooking are substantial. Even a “clean and healthy” diet may fall short. Supplements aren’t a replacement for real food, but they’re a necessary support, especially as you age.

4. Don’t wait for a disease to appear. By the time symptoms become "medical," the damage is often already done. Supplementation is most effective when started early and maintained consistently. Prevention is cheaper, safer, and more effective than waiting for decline.

5. Track your own results. If you begin supplementing, monitor your energy, sleep, digestion, skin, mood, and cognition over several weeks. Most people report measurable improvement when correcting long-standing deficiencies.

6. You can’t undo twenty years of damage in twenty days. It may take anywhere from a few months to up to one year to feel the full impact of quality supplementation, because that’s how long it takes for structural metabolism to renew most of your internal organs, assuming no irreversible damage has already occurred.

7. It’s never too late to start. Even if you’ve been dealing with chronic symptoms for years, your body retains a remarkable capacity for repair and regeneration, provided you supply it with the raw materials to do so. While some damage may be permanent, much of what we think of as “aging” is simply the result of long-standing nutrient deficiencies. Replenishing key vitamins and minerals can restore energy, sharpen cognition, improve resilience, and slow down or reverse the progression of many chronic conditions.

To summarize, your health isn’t determined by luck, genetics, or age alone, but by what your body does and doesn’t receive from diet and supplements. The information in this article is meant to give you clarity and control in a world that too often treats vitamins as an afterthought. Whether you’re trying to stay well, recover from illness, or simply feel like yourself again, the right supplments can make all the difference. Start where you are and give your body what it needs to repair, restore, and thrive. What you saw is what you get!

Author's Note

I learned most of the things you read about above in the early 1970s while attending medical university to complete my pharmacy degree. During my pharmacy residency, I dispensed all of the vitamins mentioned in this article and took them myself. That was almost fifty years ago.

My education and knowledge have served me well. At 70, I am disease-free, drug-free, pain-free, normal weight, and still recognizable to people who knew me five decades ago. Most importantly, my memory is intact, my writing is better than ever, and while most of the people I knew back then had already retired, I still enjoy working full-time and have zero plans to retire.

None of that would have been possible without taking quality vitamins for the past 30 years. Not for me. Not for my wife. Not for the relatives who followed our lead. And not for the tens of millions of others who figured out this simple concept on their own.

I hope this information will have a similar impact on your well-being as the knowledge shared on this page had on mine.

If this free article gave you insight into a topic rarely covered by mainstream medical media objectively, that’s no accident. I work independently and have no financial ties to pharmaceutical companies, hospitals, or institutional sponsors.

That independence allows me to present the facts without having to serve anyone’s agenda. If you find this approach valuable for your well-being, the best way to support my work is by sharing this article with others.

Every repost, forward, or mention helps amplify the reach and makes future work like this possible. Thank you for taking the time to read and for supporting my work!