This guide to vitamins discusses both vitamins in supplements as well as vitamins in real, natural food. Essential in the body, vitamins must be consumed through the diet in the form of nutrient-rich foods including powerhouse fruits and vegetables and grains or through multivitamin supplements.

Under the category of micronutrients falls vitamins which are necessary in small amounts for the body to function.  Vitamins are naturally-occurring components found in food that provide structural and hormonal functions in our body.  The known vitamins include vitamins A, C, D, E, K, and the B vitamins (thiamin, riboflavin, niacin, pantothenic acid, biotin, vitamin B6, vitamin B12, and folate/folic acid).  More vitamins may exist; we just don’t know of them yet.

Water-Soluble vs Fat-Soluble

There are two different types of vitamins: water-soluble and fat-soluble.  Fat-soluble vitamins are stored in fat droplets that travel through the lymph system circulating in the body whereas water-soluble vitamins are not stored, therefore the body immediately uses them.  One reason that we need to consume fat in the diet is so we can store these fat-soluble vitamins.  Due to water-soluble vitamins being easily absorbed, the risk of overdose is quite low because the body can simply excrete them.  In contrast, fat-soluble vitamins poses a higher risk for toxicity especially when supplementing because they can accumulate in the body and are excreted at a much slower rate than water-soluble vitamins.

  • Fat-soluble: Vitamins A, D, E, and K
  • Water-soluble: B Vitamins and Vitamin C

Guide to Vitamins: How Much Do You Need?

Depending on who you ask, nutrient requirements can vary.  The Dietary Guidelines for Americans (DGA) provides nutrient-rich food and drink recommendations for Americans with the goal to promote overall health, prevent chronic disease, and help people maintain a healthy weight.  These guidelines are based on the average American so they do not perfectly align with each individual needs.  Additionally, nutrition throughout one’s lifespan changes based on age, sex, activity level, and disease states so it is important to note that nutrition is individualized.

An analysis by The National Health and Nutrition Examination Survey (NHANES) from 2007 to 2010, found people in the United States had usual vitamin intakes from all food sources (excluding supplements).

Figure 1 has the Estimated Adequate Requirement (EAR) for certain vitamins.  The figure shows the percent of the sample population that fall below the EAR for each specified vitamin as defined by the DGA. Included in the DGA, the EAR is a value that is estimated to meet the nutrient requirement of half the healthy individuals in a specific age and gender group.

The top five most commonly under-consumed vitamins include Vitamin D (94%), E (89%), Magnesium (52%), Calcium (44%), and A (43%).  It is likely these vitamins are under consumed due to poor eating patterns like consuming excess sodium, saturated fat, refined grains, added sugars, and, in general, fewer nutrient-dense foods than suggested.

Figure 1: The Percent of the Population Falling Below the EAR for Micronutrients

A Guide to Vitamins

Source: What We Eat in America, NHANES 2007-2010

Pros and Cons of Vitamin Supplementation

Vitamins are essential for health and therefore supplementation may be necessary given the individual.  For example, if a person has a genetic disorder that prevents their body from absorbing fat properly, they may become deficient in fat-soluble vitamins and therefore, supplementation would be beneficial.

Edward Giovannucci from Harvard School of Public Health researches the impact of Vitamin D on our body.  Professor Giovannucci research suggests supplementing with Vitamin D reduces the risk of cancer, bone fractures, and Multiple Sclerosis.  However, supplementing vitamins is not always necessary and should be used with caution.  The US Food and Drug Administration (FDA) does not regulate supplements so a supplement can claim it contains vitamins even if it doesn’t.  It is best to do research on reputable testing companies like or which test supplements and rank them according to their quality.

Vitamins and Their Function

Listed below you will find the vitamin, the role the vitamin plays in the body, and natural remedies of vitamins as rated by scientific evidence through Natural Medicines Brand Evidence-based Rating (NMBER).  Due to vitamins being associated with fighting diseases, supplemental use of vitamins is quite common; therefore the NMBER rating system is a research-based reference guide for effective supplementation.

Table 1 below summarizes potential benefits of fighting health complications through both food and nutrient supplementation. The natural remedy listed below are only those with a grade of “A” meaning there is strong evidence to support the remedy; in contrast, a grade of “F” has very weak scientific evidence. More remedies may exist but with less supportive evidence.  We researched the highest quality vitamin supplements and provided a link to each in the table below.

Disclosure – The table below includes affiliate links. We earn a small commission at no extra cost to you if you purchase through that link. With or without an affiliate program, we still highly recommend these high quality vitamin supplements based on our research. However, supplements should never replace a nutrient rich diet. Thank you for the support, but feel free not to use the links.

Table 1: Vitamins functions in the body and their remedies 

Vitamin Function in the Body Natural Remedy through supplementation
Vitamin A (retinol) Cell growth, cell and tissue differentiation, vision, development, overall function of the immune system, and survival. Acne, anemia, acute promyelocytic leukemia (cancer of blood and bone marrow, treatment), sunburn, dry eyes and eye disorders
Vitamin C (ascorbic acid) Growth and repair of tissues, collagen formation, helps absorb iron, and acts as an antioxidant. Scurvy
Vitamin D Helps the body absorb and retain calcium and phosphorus, both critical for building bone. Kidney Disease, Osteomalacia (bone softening in adults), Rickets (bone weakening in children), Thyroid complications
Vitamin E Antioxidant function, immune function, cell signaling, regulation of gene expression, and other metabolic processes. Vitamin E Deficiency is rare
Vitamin K Maintaining bone strength and blood clotting. Supplemental Doses may be harmful
Vitamin B1 (Thiamin) Many body functions, including nervous system and muscle function, the flow of electrolytes in and out of nerve and muscle cells, digestion, and carbohydrate metabolism. Metabolic Diseases associated with genetic disorders
Vitamin B2 (Riboflavin) Functions as an antioxidant and helps deliver oxygen to cells. Needed in small amounts; deficiencies are rare
Vitamin B3 (Niacin) Functions in sex and stress-related hormones in the adrenal glands and other parts of the body; helps improve circulation, and has been shown to suppress inflammation. High Cholesterol, Pollegra
Vitamin B5 (Pantothenic Acid) Aids in the digestive tract, helps break down carbs. They are needed in only small amounts and are usually available in the foods that you eat
Vitamin B7 (Biotin) Necessary for forming fatty acids and glucose, which are used as fuels by the body; also helps in the metabolism of amino acids and carbohydrates. They are needed in only small amounts and are usually available in the foods that you eat
Vitamin B6 Helps make several neurotransmitters, needed for normal brain development and function, and helps the body make the hormones serotonin and norepinephrine, and melatonin. Anemia, Preventing adverse effects in people taking cycloserine
B12 (cobalamin) Maintains healthy nerve cells, and helps in the production of DNA and RNA, the body’s genetic material. Megaloblastic anemia
Vitamin B9 (Folate: naturally-occurring in foods, Folic acid: supplements) Aids production of DNA and RNA, the body’s genetic material, and is especially important when cells and tissues are growing rapidly, such as in infancy, adolescence, and pregnancy; also works closely with vitamin B12 to help make red blood cells and help iron work properly in the body. Anemia, Heart Disease, Prevention of pregnancy complications (birth defects)9


Foods Rich in Vitamins

Sources of Food comes from the University Of Maryland, School of Medicine Medical Reference Guide Complementary and Alternative Medicine Guide

Vitamin A: Beef, calf, chicken liver, eggs, fish liver oils, dairy products including whole milk, whole milk yogurt, whole milk cottage cheese, and butter.

Vitamin C: Oranges, green peppers, watermelon, papaya, grapefruit, cantaloupe, strawberries, kiwi, mango, broccoli, tomatoes, brussels sprouts, cauliflower, cabbage, and citrus juices.  Raw and cooked leafy greens (turnip greens, spinach), red and green peppers, canned and fresh tomatoes, potatoes, winter squash, raspberries, blueberries, and cranberries.

Vitamin D: Cod liver, fatty fish including salmon, mackerel, tuna, sardines, herring, eggs.

Vitamin E: Liver, eggs, nuts (almonds, hazelnuts, walnuts), sunflower seeds, dark green leafy vegetables including spinach and kale, cereal grains, beets, collards, sweet potatoes, avocado, asparagus, yams.

Vitamin K: Beef liver, green tea, turnip greens, broccoli, kale, spinach, cabbage, asparagus, and dark green lettuce.

Thiamin: Beef, brewer’s yeast, legumes (beans, lentils), milk, nuts, oats, oranges, pork, rice, seeds, wheat, whole-grain cereals, and yeast

Riboflavin: Brewer’s yeast, almonds, organ meats, whole grains, wheat germ, wild rice, mushrooms, soybeans, milk, yogurt, eggs, broccoli, brussels sprouts, spinach.

Pantothenic acid: Brewer’s yeast, corn, cauliflower, kale, broccoli, tomatoes, avocado, legumes, lentils, egg yolks, beef organ meats, turkey, duck, chicken, milk, split peas, peanuts, soybeans, sweet potatoes, sunflower seeds, whole-grain breads and cereals, lobster, wheat germ, and salmon.

Niacin: Beets, brewer’s yeast, beef liver, beef kidney, fish, salmon, swordfish,una, sunflower seeds, peanuts

Biotin: Brewer’s yeast; cooked eggs, especially egg yolk; sardines; nuts (almonds, peanuts, pecans, walnuts) and nut butters; soybeans; other legumes (beans, blackeye peas); whole grains; cauliflower; bananas; and mushrooms.

B6: Chicken, turkey, tuna, salmon, shrimp, beef liver, milk, cheese, lentils, beans, spinach, carrots, brown rice, bran, sunflower seeds, wheat germ, bananas, whole grain flour

B12: Fish, shellfish, dairy products, organ meats (liver and kidney), eggs, beef, pork.

Folate: Cereals, baked goods, leafy vegetables (spinach, broccoli, lettuce), okra, asparagus, fruits (bananas, melons, lemons), legumes, yeast, mushrooms, organ meat (beef liver, kidney), orange juice, and tomato juice.

Vitamin Optimization in Foods

Designing diet patterns including a wide variety nutrient-rich foods will provide you with the vitamins to maintain or improve overall health.  Colorful foods like fruits and vegetables, are not only full of vitamins but are inexpensive in comparison to supplements.  For instance, One serving of spinach contains 8 different vitamins and kale contains 9 vitamins, whereas a banana has 3 out of the 13 vitamins.  Eggs provide a variety of B vitamins which help us keep our energy up.

A good source of protein rich in vitamins is soybeans containing 5 vitamins.  This is not an exhaustive list of vitamins in each food; more vitamins may be present in foods but in much smaller amounts.  The best way to understand the vitamin content in foods is to compare the amount of vitamins in a serving to the Daily Value (DV).  Lastly, just because a food label claims it contains an array of vitamins, it does not guarantee that the vitamins present are rich sources.  To understand more about reading a food label, The American Heart Association provides a straight-forward explanation.

What Happens When You Don’t Get Enough Vitamins?

When the body becomes deficient in a vitamin, deficiencies can manifest themselves in physical ailments. For instance, weak nails can indicate a Vitamin B deficiency; however, physical signs are not always accurate and not always seen.  Some deficiencies remain hidden and will have no signs but that doesn’t mean you shouldn’t be concerned.  Vitamins help our immune system functioning and play a role in antioxidant function which, in turn, keeps us healthy by fighting diseases.  If you are confused about being deficient, getting blood work done will ease those worries.

Take-Home Message

Vitamins are critical to manning overall health, fighting diseases, and maintaining a healthy weight.  It is best to consume a wide variety of real foods rather than relying on supplements alone to satisfy nutrient requirements.  Nutrient-dense foods that have a high ratio of vitamins to energy density are your best sources; therefore, fruits and vegetables offer a variety of vitamins and overall health benefits to best fuel your body.  If you are unsure you are reaching your individual requirements, contact your doctor to evaluate your current nutritional status.  Being proactive is the first step to better overall health!


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