Basic Vitamins

Vitamin A

Vitamin A has never basked in the limelight or topped the list of popular nutrients, but its benefits to the body have a substantial impact on health. Vitamin A deficiency is a perpetual problem in many countries. By knowing the pros of this nutrient, as well as its sources, patients can successfully maintain healthy eyes, bones and skin.

Good eyesight and this nutrient go hand-in-hand. Poor night vision is strongly associated with a lack of vitamin A, as is dry eye [Source: Johnson, Rengstorff]. This nutrient in the form of beta-carotene has been shown to benefit patients with macular degeneration as part of a multivitamin containing 500 mg of vitamin C, 400 IU of vitamin E, 15 mg of beta-carotene, 80 mg of zinc and 2 mg copper [Source: AREDS].

Acne and scaliness of the skin is associated with vitamin A deficiency [Source: Guyton and Hall]. The benefits of this vitamin in relation to the skin extend to prevention of infections. The World Health Organization has included vitamin A supplementation in the management of measles infection, as it significantly lowers the risk of death from the condition [Source: WHO]. One trial also demonstrated a benefit of vitamin A supplementation for patients with heavy menstruation [Source: Lithgow]. Those who have undergone a gallbladder removal may have trouble absorbing fat-soluble vitamins, including A, D, E and K. Poor digestion, absorption and dietary choices can heighten the need for general supplementation.

Beneficial elements are best obtained through food sources high in beta-carotene, a carotenoid. Carotenoids, of which there are more than five hundred known, are chemicals derived from plants. They give fruits and vegetables their pigment and, as they are studied more, are found to contain respectable levels of antioxidants. Beta-carotene is very closely related in structure to vitamin A and is one of the few carotenoids that can be converted to vitamin A in the liver.

Vitamin A is found in animal products such as liver, eggs and cow milk, while beta-carotene is in many fruits and vegetables, like carrots, apricots, spinach, kale and cabbage. As they contain a buffet of nutrients, eggs, spinach and cabbage should be a regular component of your diet.

As a supplement, both vitamin A and beta-carotene are acceptable. Most multivitamins already include one of these forms. Dosing for vitamin A commonly ranges from 5,000-15,000 IU (international units). Those who eat more varieties, specifically colors, of vegetables have less need for supplementation, as do the elderly. An excess of vitamin A has been linked to birth defects in some animals. To be safe, when supplementing during pregnancy don’t ingest more than 10,000 IU a day [Source: Mills]. Prenatal vitamins typically provide less than this to allow for vitamin A and beta-carotene in the diet.

There’s a very high rate of tolerance for vitamin A. Clinically, doctors have used up to 100,000 IU a day to treat infections. Dosages such as this should only be done under a doctor’s supervision and for brief periods of time (days). Any female who has even the slightest inclination of pregnancy should not consume this high level of vitamin A. Signs of vitamin A toxicity include joint pain, muscle aches and dry skin. Toxicity from a daily multivitamin is rare. Some data suggests a link of excessive amounts of this nutrient to osteoporosis [Source: Melhus].

B Complex Vitamins

Just as you’d find in a traditional household, the B complex family of vitamins includes several different vitamins grouped together. Essential to proper body function and optimal health, each has its own individual function, but many rely on other vitamins in the family to function properly.

A well-balanced nutrition plan, high in fresh fruits, vegetables, beans, and whole grains, along with a healthy lifestyle, should already include the necessary amounts of B complex vitamins. That said, there are instances when supplementation is necessary. For example, poor digestion from long-term use of antibiotics or acid-suppressing medications will deter adequate absorption of many vitamins and minerals from food sources. Those who engage in high-stress lifestyles, have poor eating habits, smoke, suffer from alcoholism or ingest certain medications might need another source of these vitamins.

Because these vitamins often function in such a coordinated fashion, and being low in a specific B vitamin puts one at risk for deficiency in others, it’s best to supplement with the entire complex. If you’re striving for a specific B vitamin in a higher dose, continue to take a foundation of B complex for additional support.

Pay special attention to folic acid and vitamin B-12, as a deficiency of these can lead to anemia, nerve problems and an elevated level of homocysteine, an independent risk factor for heart disease and other inflammatory diseases. Levels of these vitamins can, and should, be measured by a physician to determine the need for supplementation. Heed the levels of serum B-12 and red blood cell folate (RBC folate). If supplementing folic acid, always take B-12 supplementation as well. The intake of folic acid in the face of vitamin B-12 deficiency can mask anemia, leading to permanent nerve damage.

A Review of B Vitamins:

Thiamin (vitamin B-1)

  • What it does: A requirement for proper energy production in the brain and essential for nerve cell function.
  • Food sources: Soybeans, nuts, whole grains and seeds.
  • Causes of deficiency: Inadequate dietary intake, excessive alcohol consumption, (which destroys thiamin) and the use of medications like furosemide and phenytoin.
  • Supplementation: 50-100 mcg daily.

Riboflavin (vitamin B-2)

  • What it does: Critical to the production of energy.
  • Food sources: Leafy green vegetables, nuts and mushrooms.
  • Causes of deficiency: Inadequate dietary intake or use of oral contraceptives.
  • Supplementation: 5-10 mg daily as part of a B-complex supplement. Evidence-based therapy: A study in Neurology, the official journal of the American Academy of Neurology, in 1998 showed that a daily dosage of 400 mg of riboflavin over three months led to a reduced frequency of migraine headaches.

Niacin (vitamin B-3)

  • What it does: Allows for the proper functioning of more than 50 enzymes and aids in the body’s production of energy.
  • Food sources: Whole wheat, almonds and seeds.
  • Causes of deficiency: Inadequate dietary intake.
  • Supplementation: General supplementation is not usually necessary. Those with blood flow problems, like Raynaud’s phenomenon or claudication, should try 100 mg twice daily, with food. The preferred form is inositol hexaniacinate. Sustained-release niacin should never be used as it may be toxic. Flush-free products are not effective.
  • Evidence-based therapy: Multiple studies have proven that the use of niacin lowers blood cholesterol. Treatment doses are 1-4 grams daily, but should be taken only under the supervision of a physician, as liver inflammation and flushing are common side effects.

Pyridoxine (vitamin B-6)

  • What it does: Assists in making proteins, hormones, and the chemicals that carry signals between nerves called neurotransmitters. Also strongly linked with magnesium.
  • Food sources: Walnuts, beans, bananas and avocados.
  • Causes of deficiency: Inadequate dietary intake. Reports claim up to 71 percent of men and 90 percent of women have inadequate levels. Several medications are associated with vitamin B-6 depletion: Antibiotics, hydrochlorothiazide, estrogen, oral contraceptives, furosemide and Torsemide.
  • Supplementation: 5-10 mg daily as part of a B complex supplement.
  • Evidence-based therapy: Proven treatment for morning sickness at a dose of 30 mg daily. A dosage of 50 mg twice daily can improve the symptoms of carpal tunnel syndrome, assist in decreasing homocysteine levels and help prevent Alzheimer’s disease.

Folic Acid or Folate (vitamin B-9)

  • What it does: Important for cell division and many other body processes.
  • Food sources: Dark, leafy vegetables, beans and asparagus.
  • Causes of deficiency: Medications like antacids, oral diabetes medications, oral corticosteroids, oral contraceptives, anti-inflammatory medication or hydrochlorothiazide.
  • Supplementation: A dose of 400 mcg daily is sufficient, and essential for all females of reproductive age.
  • Evidence-based therapy: 400 mcg daily is essential for the prevention of neural tube defects (problems with the developing brain or spinal cord) and other birth defects in developing fetuses. Also, along with vitamin B-12 supplementation, it decreases levels of homocysteine in the body. Elevated homocysteine levels correlate with an increased risk of heart disease and Alzheimer’s disease.

Cyanocobalamin (vitamin B-12)

  • What it does: Essential for normal activity of the nerves. Deficiency can lead to anemia, and if supplementation of folic acid occurs in the face of deficiency, permanent nerve damage can result.
  • Food sources: Salmon, tuna, eggs and cheese.
  • Causes of deficiency: Decreased levels of stomach acid (any person on acid lowering medication and 10-20 percent of people 65 years of age and older. Low levels are also related to medications like metformin, oral contraceptives and several types of antibiotics.
  • Supplementation: Daily supplementation (essential for vegans and those on medications that can lead to deficiency) is 25-100 mcg daily. Those found to be deficient should take a dosage of 1000-2000 mcg daily (this includes those with pernicious anemia previously told to get B-12 in shot form only). The preferred form of vitamin B-12 supplementation is methylcobalamin sublingually (under the tongue).

Vitamin B-6

A vitamin is, by definition, a nutrient the body cannot make, but needs for numerous daily metabolic functions. As a multitasking powerhouse, vitamin B-6, or pyridoxine, is no exception.

Though B-6 plays several roles, its influence on the blood marker homocysteine may be most important. As part of the metabolic turnover of certain proteins and amino acids, everyone has homocysteine in their blood. However, research is mounting that this byproduct may be a risk factor for stroke, blood vessel disease, osteoporosis, depression, dementia, macular degeneration and osteoporosis. Elevated levels in the bloodstream can be successfully treated with vitamins B-12, folic acid and B-6 in combination.

On top of its positive role in brain, cardiovascular, mood and bone health, multiple studies have linked higher B-6 levels in the blood to lower colon cancer rates [Source: Wei, Kune, Matsubara]. It has also shown benefit with PMS symptoms and depression [Source: Proctor, Hvas]. Many of the neurotransmitters (signaling chemicals between nerves) that affect pain and mood are made by processes that require B-6 [Source: Kemper]. Medications used to treat schizophrenia often produce significant, limiting side effects. Research has documented a protective effect of B-6 against many of these [Source: Miodownik].

Commonly, this vitamin is paired with magnesium for better results, particularly when treating carpal tunnel, kidney stones and even autism. The data regarding B-6 and carpal tunnel is limited and doesn’t demonstrate strong improvement, but since B-6 is tolerated well, it’s often suggested as an adjunct treatment [Source: Holm].

Kidney stone sufferers should consider the B-6/magnesium combination as a preventative measure [Source: Rattan]. The majority of the benefit may actually come from the magnesium, but some patients do gain further help from B-6 [Source: Assimos]. The treatment for autism is extremely complicated. That said, some research has found improvement in social interaction and communication in patients with developmental delay when given B-6 and magnesium in combination [Source: Mousain-Bosc].

Vitamin B-6 deficiency symptoms include nausea and vomiting, dermatitis (inflammation of the skin) and even seizures. Isoniazid, hydralazine, penicillamine and oral birth control pills are all medications thought to decrease levels of this nutrient in the body.

Dietary sources of B-6 include proteins such as fish, beef and chicken, as well as bananas, garbanzo beans and potatoes. Many fortified cereals and grain products often contain B-6 also.

As a supplement, this vitamin is commonly sold by itself as pyridoxine, or in a more active form, called pyridoxal-5-phosphate. The dosage of B-6 is typically 10 mg for health maintenance. Treatment dosages range from 50-100 mg for PMS, carpal tunnel, kidney stones and elevated homocysteine, and 100-400 mg for those with schizophrenia. These dosages should be coordinated with a physician. B-6 appears very safe and tolerable as a primary or additional treatment. Magnesium at a dose of 400-600 mg daily, taken along with B-6, may enhance the success of the treatment.

Some side effects of B-6 may include changes in the nerve function of the hands and feet, leading to decreased sensation or change in gait. These symptoms usually occur at 2,000 mg or more daily and dissipate when the dosage is decreased. B-6 may have a blocking effect on the Parkinson’s disease drug L-dopa, and may lessen the efficacy of antiseizure medications phenobarbital and phenytoin.

Vitamin C

Vitamin C is perhaps one of the most recognized nutrients, particularly during cold and flu season. From the support of a known Nobel Prize winner, to its use by the British navy, this immune supporter has never lacked in notoriety.

Supplementation of vitamin C can decrease the intensity of cold and flu symptoms and be safely combined with other nutrients to maintain a strong immune system during fall and winter months.

Two-time Nobel Prize winner Linus Pauling was a leading proponent of vitamin C, advocating its use until his death at 93. Pauling suggested high dose supplementation for the treatment of heart disease, and improved survival for patients with various types of cancer [Source: Cameron]. Repeat studies have failed to show this same benefit, though many have argued that follow-up studies were significantly flawed in execution. Research is now underway to look at the role of intravenous vitamin C with cancer treatments. Many integrative doctors advocate this use for its high safety record and successful documented cases.

Vitamin C deficiency, known as scurvy, was one of the earliest recognized deficiencies in traditional medicine. As European explorers ventured across the oceans on long voyages, sailors began to experience significant symptoms such as poor wound healing. Vitamin C is necessary to help manufacture collagen, a building block of structural support needed throughout the body [Source: Guyton and Hall]. Scurvy can also cause weak bones, small blood vessels to break more easily, and can affect the health of the gums. The sailors of the past suffered from limited food sources of vitamin C and refrigeration. The British navy eventually learned that the sailors would stay healthy by eating fruit.

To date, conventional medicine has not fully embraced Pauling’s view of vitamin C as a treatment for heart disease. Given the integral role of vitamin C in collagen formation, particularly in relation to blood vessels, it is still possible Pauling was correct. Larger studies are needed to explore this method. Data shows that vitamin C can help with the function of blood vessels in patients with diabetes, hypertension and heart disease [Source: Ting, Taddei, Erbs].

Food sources of vitamin C are vast and include fruits and vegetables, such as oranges, broccoli and red peppers. Fortunately, these are foods that provide not only vitamin C, but several other nutrients as well.

Dosing for vitamin C depends on the patient’s needs. Routine dosing typically ranges from 500-1,000 mg per day. Many integrative physicians suggest increasing the vitamin C dosage to “bowel tolerance” to treat colds and other viral infections, or even in chronic health conditions like fatigue or cancer. Labels may include various forms such as Ester-C, ascorbic acid, or Ascorbyl palmitate. No single type of vitamin C stands out above the rest and choices should be made based on personal preference.

Bowel tolerance means that a dosage of vitamin C (typically 500-1,000 mg) can be taken every 1-2 hours until symptoms of loose bowels or bloating occur, at which point consumption should be stopped for that day. On the next day, the dosage should be decreased slightly so that bowel-related side effects are not repeated. This level of treatment can continue until symptoms have resolved.

In those battling constipation, a similar supplementation strategy can be followed. In fact, vitamin C is commonly used to treat constipation because of its benefits to the immune system.

Bloating and loose bowels are known side effects of excessive vitamin C. This typically occurs if 1,500 mg or more is taken at one time. Vitamin C can increase the absorption of iron from food or supplements. Those with a history of excess iron may need to be cautious with intake.

Vitamin D

Vitamin D is fast becoming one of the most important supplements attributed to overall wellness, though it’s better described as a sun-derived pro-hormone rather than a vitamin. For years, it was strictly thought of in relation to bone health due to its role in the maintenance of calcium balance. Though it does balance calcium, it provides many other benefits to the body as well. Rarely few weeks pass without a new study surfacing showing the benefits of adequate vitamin D levels. It serves a number of vital roles in the body: Assisting in cell function and growth, maintaining immune function, reducing inflammation and keeping bones strong.

With this array of benefits, it’s easy to see why studies have linked vitamin D deficiency to:

  • Obesity
  • Diabetes
  • Multiple Sclerosis
  • Arthritis
  • Depressed immune system
  • Osteoporosis
  • Increased risk of cancer (breast, prostate, colon, pancreas, ovary)
  • Hypertension
  • Heart attack
  • Stroke
  • Muscle weakness and deep muscle pain
  • Seasonal Affective Disorder
  • Preeclampsia

Vitamin D is known as the "sunshine vitamin," since our skin manufactures it upon exposure to UV-B rays. Darker pigmented skin absorbs less rays, and therefore, makes less vitamin D. The pro-hormone can be obtained from food sources like fatty fish (salmon), egg yolks, fortified milk and cereals as well.

Nearly 75-80 percent of the population suffers from less than optimal levels of vitamin D as a result of insufficient diet, excessive time spent indoors, living too far north of the equator for adequate sunlight and the widespread use of sunscreen. Sunscreen is important to prevent sunburn, which increases the risk of certain skin cancers, but most children and adults should try to be in the sun for 15-20 minutes a day without it, with as much skin showing as possible.

In order to begin supplementation with vitamin D, first detect blood levels. Differences in diet, lifestyle, time spent outdoors and genetic differences in how the body responds to sunlight mean that one particular dose is not best for everyone. Always take into account the season in which the level is being checked. A normal level in July is not helpful for someone that suffers from Seasonal Affective Disorder (winter blues). Be certain your physician is familiar with vitamin D, and they are using a reputable lab test. The level of 25-hydroxy vitamin is most important, with the goal at 50-60 ng/mL.

If blood levels are unknown, healthy adults should take at least 1,000-2,000 IU daily. Anyone with a risk of, or suffering from, any of the illnesses mentioned above would be best served finding out their vitamin D blood levels. Most people with low levels of vitamin D are able to reach their goals by taking 4,000-5,000 IU for a period of 4-6 weeks. It may be beneficial to take higher doses during low sun months (usually September through April), backing down during the summer.

There are two main forms of vitamin D: Vitamin D-3 (cholecalciferol) and D-2 (ergocalciferol). Most vitamin D-fortified foods and supplements use the less active and potentially toxic form, D-2. Always be certain you’re taking vitamin D-3.

What about children?Vitamin D is important for infants and children as well. Infants fed with formula are getting enough vitamin D. Children who consume at least two glasses of vitamin D-fortified milk daily are as well. For breast-fed infants 2 months of age and older, and any children not consuming milk, parents should ensure their child gets at least 200 IU of vitamin D daily.

When is the sun not strong enough?For a rough guideline, when your shadow is longer than you are tall, the sun is no longer capable of stimulating enough vitamin D production in the skin.

Are there any side effects?Vitamin D is thought to be a very safe supplement, especially when taken in doses up to 5,000 IU per day. If taking higher doses, you should be working in coordination with a physician who is monitoring your blood levels. High level supplementation can put you at risk of hypercalcemia, an elevated calcium level. Side effects such as nausea, vomiting, weakness or headaches are possible, and should be brought to the attention of a physician.

Vitamin E

For many consumers, the myriad of supplements crowding store shelves generates more confusion than anything. Which vitamins do I really need? Can any of these harm me? To add to the confusion, recent reports have suggested possible harm from taking vitamin E, a supplement previously thought of as a safe standard. Other reports maintain the vitamin’s safety. In an effort to ease some of the nutrient-related befuddlement, this article will address the benefits of extra vitamin E and its preferred sources.

Vitamin E acts primarily as an antioxidant. Many bodily processes result in the production of free radicals, which can lead to cellular stress and inflammation, thought to be key factors related to heart disease and cancer. Antioxidants provide protection by neutralizing these free radicals.

Vitamin E actually has multiple forms, including alpha-, beta-, gamma- and delta-tocopherols. Alpha-tocopherol is the form most often found in vitamin E supplements and within the body. Alpha-tocopherol will often be listed as d-alpha-tocopherol or dl-alpha-tocopherol. The dl form is the more synthetic, less preferred, version of the two. Though alpha-tocopherol is the most common form of vitamin E in the body, the beta, delta and gamma forms are needed as well. Any time you supplement with vitamin E, look for the d-alpha form along with mixed tocopherols (the term for additional forms). Take this nutrient with food.

As with nearly all vitamins and minerals, strive for adequate and consistent dietary intake of vitamin E. Main food sources include whole grains, leafy vegetables, nuts and seeds.

Clinically, this nutrient is used for both prevention and treatment. Please consider taking vitamin E if you suffer from, or are at risk for, the following:

  • Restless legs. 400-800 IU has been shown to help with leg cramps.
  • Hot flashes. Patients can try 800 IU a day, with food. This is best for patients with a history of breast cancer who do not have the option of hormone-based treatments.
  • Brain health. 400 IU daily, with food. The brain is an organ that is comprised of a significant amount of fat. Vitamin E is thought to be part of the team that helps prevent damage to fat, in the brain and elsewhere.
  • General wellness. 400 IU daily, with food.

Though recent research has cast vitamin E as a dangerous supplement, it’s important to note whether the study used only the alpha form of vitamin E, or if it examined the additional forms as well [Source: Falloon]. A 19-year trial of 29,000 male smokers looked at the effects of vitamin E on various causes of death [Source: Wright]. Men with the highest blood values of vitamin E had notably decreased rates of prostate and lung cancer, as well as stroke. These results certainly support the side for supplementation. Other studies have suggested that most Americans are not getting adequate amounts of vitamin E in their diets [Source: Traber, Maras]. Based on the aforementioned study, prevention of many chronic illnesses could be helped by maintaining higher values of vitamin E.

Vitamin K

Like vitamin D, research related to vitamin K has rapidly grown in recent years, emphasizing the importance of supplementation for certain populations. These studies have explored bone benefits and vascular health, with a focus on vitamin K-2, found in certain fermented foods and produced in healthy digestive systems. Most multivitamins contain the older form, vitamin K-1, which is easily obtained in broccoli and green leafy vegetables. This discussion will focus on the studies supporting vitamin K-2.

Vitamin K comes in many forms and from various sources. Plants, such as vegetables, provide K-1, or phylloquinone. In recent years, vitamin K-2 has been divided into two groups: menaquinone-4 (MK-4) and menaquinone-7 (MK-7). Vitamin K-3 is the synthetic form.

MK-4 and MK-7 are found in fermented cheeses and a fermented soy product called Natto. It is also made by bacteria in the intestinal tract [Source: Plaza]. Because of this, those with chronic bowel problems, like diarrhea or inflammatory bowel conditions, are commonly at risk of vitamin K deficiency.

Vitamin K signals the protein osteocalcin, which aids in the ongoing bone remodeling process [Source: Askim, Okano]. Treatment with vitamin K-2 has shown effectiveness in fighting bone loss, especially when used with conventional treatments [Source: Kaneki, Kishimoto, Iwamoto].

Vitamin K is also being recognized for its role in vascular health. Inflammation is thought to be the trigger that initiates injury in the blood vessels. Atherosclerosis, commonly referred to as a hardening of the arteries, or plaque, is thought to succeed inflammation. This hardening includes calcium deposits in the artery walls. Vitamin K-2 intake can actually help prevent calcium build up in the blood vessel walls [Source: Schurgers]. Further research has documented a lowered risk of heart disease with higher vitamin K-2 intake [Source: Geleijnse].

Although generally safe, there are a few cautions tied to this nutrient. Vitamin K was originally studied for its role in blood clotting. The drug warfarin, used for the prevention of blood clot formation, inhibits vitamin K’s role in the blood clotting system. Patients on warfarin have to be careful with their vitamin K intake, as it will lessen the effect of the medication. Consider consulting a doctor prior to supplementation.

Vitamin K-2 presents exciting new possibilities for bone and blood vessel health. The decision to supplement with vitamin K should be based on a person’s own risk and family history. Adding this nutrient to your daily regimen is a smart option for those at risk for osteoporosis and heart disease.

Vitamin K-1 is commonly found in multivitamins, but the K-2 form is recommended for those with cardiac issues. The dosage of MK-4 compared to MK-7 is substantially varied. This is because the body absorbs MK-7 better. MK-4 isn’t ineffective; it just requires a significantly higher dosage to provide equal benefit. Caution is advised in regards to the form you choose, so proper dosages are observed.

Dosage for common forms:

  • K-2. Take both forms with food.
  • MK-4. 45 mg or 45,000 mcg daily.
  • MK-7. 150 mcg daily.

Lots More Information

Related Articles

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