Your Nutrients

Acetyl-L-carnitine is similar in form to the amino acid L-carnitine and also has some similar functions, such as being involved in the metabolism of food into energy. The acetyl group that is part of acetyl-L-carnitine contributes to the production of the neurotransmitter acetylcholine, which is required for mental function.

Acetyl-L-carnitine is a molecule that occurs naturally in the brain, liver, and kidney. It is also available as a dietary supplement.

Acetyl-L-carnitine levels may decrease with advancing age. However, because it is not an essential nutrient, true deficiencies do not occur.

Age-related cognitive decline Alzheimer’s disease Cerebellar ataxia, degenerative Depression (for elderly people) Down’s syndrome Erectile dysfunction (in combination with L-carnitine) Macular degeneration (in combination with fish oil and coenzyme Q10) Type 1 diabetes Type 2 diabetes Amenorrhea Male infertility Peripheral neuropathy

Side effects from taking acetyl-L-carnitine are uncommon, although skin rash, increased appetite, nausea, vomiting, agitation, and body odor have been reported in people taking acetyl-L-carnitine. Certain medicines may interact with acetyl-L-carnitine. Refer to drug interactions for a list of those medicines.

Most research involving acetyl-L-carnitine has used 500 mg three times per day, though some research has used double this amount.

Potassium is an essential mineral needed to regulate water balance, levels of acidity, blood pressure, and neuromuscular function. This mineral also plays a critical role in the transmission of electrical impulses in the heart.

Most fruits are excellent sources of potassium. Beans, milk, and vegetables contain significant amounts of potassium.

So-called primitive diets provided much greater levels of potassium than modern diets, which may provide too little. Gross deficiencies, however, are rare except in cases of prolonged vomiting, diarrhea, or use of “potassium-depleting”diuretic drugs. People taking one of these drugs are often advised by their doctor to take supplemental potassium. Prescription amounts of potassium provide more than the amounts sold over the counter but not more than the amount found in several pieces of fruit.

High blood pressure (for people not taking potassium-sparing diuretics) Kidney stones (citrate in combination with magnesium citrate) Cardiac arrhythmia Congestive heart failure Premenstrual syndrome Stroke

High potassium intake (several hundred milligrams at one time in tablet form) can produce stomach irritation. People using potassium-sparing drugs should avoid using potassium chloride-containing products, such as Morton Salt Substitute®, No Salt®, Lite Salt®, and others and should not take potassium supplements, except under the supervision of a doctor. Even eating several pieces of fruit each day can sometimes cause problems for people taking potassium-sparing drugs, due to the high potassium content of fruit. Potassium and sodium work together in the body to maintain muscle tone, blood pressure, water balance, and other functions. Many researchers believe that part of the blood pressure problem caused by too much salt (which contains sodium) is made worse by too little dietary potassium. People with kidney failure should not take potassium supplements, except under careful medical supervision. Certain medicines may interact with potassium. Refer to drug interactions for a list of those medicines.

The best way to obtain extra potassium is to eat several pieces of fruit per day, as well as liberal amounts of vegetables. The amount of potassium found in the diet ranges from about 2.5 grams to about 5.8 grams per day. The amount allowed in supplements—99 mg per tablet or capsule—is very low, considering that one banana can contain 500 mg. One should not attempt to achieve higher potassium levels by taking large numbers of potassium pills. This concentrated form of potassium can irritate the stomach—a problem not encountered with the potassium in food.

Betaine hydrochloride is an acidic form of betaine, a vitamin-like substance found in grains and other foods. Betaine hydrochloride is recommended by some doctors as a supplemental source of hydrochloric acid for people who have a deficiency of stomach acid production (hypochlorhydria).

Gastric acid is produced by the parietal cells of the stomach. The acidity is quite strong in a normal stomach. In fact, the stomach can be between 100,000 and almost 1,000,000 times more acidic than water.

Some research suggests that people with a wide variety of chronic disorders, such as allergies, asthma, and gallstones, do not produce adequate amounts of stomach acid.

Acne Rosacea Asthma Chronic candidiasis Dermatitis herpetiformis Food allergies Gallstones Gastroesophageal reflux disease (GERD) Hives Indigestion Iron-deficiency anemia (as an adjunct to supplemental iron) Rheumatoid arthritis Tic douloureux Vitiligo

Large amounts of betaine HCl can burn the lining of the stomach. If a burning sensation is experienced, betaine HCl should be immediately discontinued. People should not take more than 10 grains (650 mg) of betaine HCl without the recommendation of a physician. All people with a history of peptic ulcers, gastritis, or gastrointestinal symptoms particularly heartburn should see a doctor before taking betaine HCl. People taking nonsteroidal anti-inflammatory drugs (NSAIDs), cortisone-like drugs, or other medications that might cause a peptic ulcer should not take betaine HCl. Betaine HCl helps make some minerals and other nutrients more absorbable. At the time of writing, there were no well-known drug interactions with Betaine Hydrochloride.

Betaine HCl is the most common hydrochloric acid-containing supplement. Normally it comes in tablets or capsules measured in grains or milligrams. Only people who have reduced levels of stomach acid (“hypochlorhydria”) should take betaine HCl; this condition can be diagnosed by a doctor. When appropriate, some doctors recommend taking one or more tablets or capsules, each 5–10 grains (325–650 mg), with a meal that contains protein. Occasionally, betaine (trimethylglycine) is recommended to reduce blood levels of a substance called homocysteine, which is associated with heart disease. This form of betaine is different from betaine HCl.

Folic acid is a B vitamin needed for cell replication and growth. Folic acid helps form building blocks of DNA, the body’s genetic information, and building blocks of RNA, needed for protein synthesis in all cells. Therefore, rapidly growing tissues, such as those of a fetus, and rapidly regenerating cells, like red blood cells and immune cells, have a high need for folic acid. Folic acid deficiency results in a form of anemia that responds quickly to folic acid supplementation.

Beans, leafy green vegetables, citrus fruits, beets, wheat germ, and meat are good sources of folic acid.

Many people consume less than the recommended amount of folic acid. Scientists have found that people with heart disease commonly have elevated blood levels of homocysteine, a laboratory test abnormality often controllable with folic acid supplements. This suggests that many people in Western societies have a mild folic acid deficiency. In fact, it has been suggested that increasing folic acid intake could prevent an estimated 13,500 deaths from cardiovascular diseases each year. Folic acid deficiency has also been common in alcoholics, people living at poverty level, those with malabsorption disorders or liver disease (e.g., cirrhosis), and women taking the birth control pill. Recently, elderly people with hearing loss have been reported to be much more likely to be folic acid deficient than healthy elderly people. A variety of prescription drugs including cimetidine, antacids, some anticancer drugs, triamterene, sulfasalazine, and anticonvulsants interfere with folic acid. Deficiency of folic acid can be precipitated by situations wherein the body requires greater than normal amounts of the vitamin, such as pregnancy, infancy, leukemia, exfoliative dermatitis, and diseases that cause the destruction of blood cells. The relationship between folic acid and prevention of neural tube defects is partly thought to result from the high incidence of folate deficiency in many societies. To protect against neural tube defects, the U.S. Food and Drug Administration has mandated that some grain products provide supplemental folic acid at a level expected to increase the dietary intake by an average of 100 mcg per day per person. As a result of folic acid added to the food supply, fewer Americans will be depleted compared with the past. In 1999, scientific evidence began to demonstrate that the folic acid added to the U.S. food supply was having positive effects, including a partial lowering of homocysteine levels. In the same year, however, a report from the North Carolina Birth Defects Monitoring Program suggested the current level of folic acid fortification has not reduced the incidence of neural-tube defects. Many doctors and the Centers for Disease Control in Atlanta believe that optimal levels of folic acid intake may still be higher than the amount now being added to food by several hundred micrograms per day. A low blood level of folate has also been associated with an increased risk of miscarriage. People with kidney failure have an increased risk of folic acid deficiency. Recipients of kidney transplants often have elevated homocysteine levels, which may respond to supplementation with folic acid. The usual recommended amount of 400 mcg per day may not be enough for these people, however. Larger amounts (up to 2.4 mg per day) may produce a better outcome, according to one double-blind trial. Folate deficiency is more prevalent among elderly African American women than among elderly white women.

Birth defects prevention Depression Gingivitis (periodontal disease) (rinse only) High homocysteine (in combination with vitamin B6 and vitamin B12) Pap smear (abnormal) (in women taking oral contraceptives) Pregnancy and postpartum support Schizophrenia (for deficiency) Anemia (for thalassemia if deficient) Atherosclerosis Breast cancer (reduces risk in women who consume alcohol) Canker sores (for deficiency only) Celiac disease (for deficiency only) Colon cancer (prevention) Heart attack Preeclampsia Sickle cell anemia (for lowering homocysteine levels) Skin ulcers Ulcerative colitis Alzheimer’s disease Bipolar Disorder/Manic Depression Crohn’s disease Dermatitis herpetiformis (for deficiency) Diarrhea Down’s syndrome Epilepsy Gingivitis (periodontal disease) (pill) Gout HIV support Lung cancer (reduces risk) Osteoporosis Peripheral vascular disease Psoriasis Restless legs syndrome Seborrheic dermatitis Stroke (for high homocysteine only) Vitiligo

Folic acid is not generally associated with side effects. However, folic acid supplementation can interfere with the laboratory diagnosis of vitamin B12 deficiency, possibly allowing the deficiency to progress undetected to the point of irreversible nerve damage. Although vitamin B12 deficiency is uncommon, no one should supplement with 1,000 mcg or more of folic acid without consulting a doctor. Vitamin B12 deficiencies often occur without anemia (even in people who do not take folic acid supplements). Some doctors do not know that the absence of anemia does not rule out a B12 deficiency. If this confusion delays diagnosis of a vitamin B12 deficiency, the patient could be injured, sometimes permanently. This problem is rare and should not happen with doctors knowledgeable in this area using correct testing procedures. Folic acid is needed by the body to utilize vitamin B12. Proteolytic enzymes inhibit folic acid absorption. People taking proteolytic enzymes are advised to supplement with folic acid. Certain medicines may interact with folic acid. Refer to drug interactions for a list of those medicines.

Many doctors recommend that all women who are or who could become pregnant take 400 mcg per day in order to reduce the risk of birth defects. Some doctors also extend this recommendation to other people in an attempt to reduce the risk of heart disease by lowering homocysteine levels. Since the FDA mandated addition of folic acid to grain products, many people who eat grains have followed the new recommendation of supplementing only 100 mcg of folic acid per day. However, studies have found that this amount of folic acid is inadequate to maintain normal folate levels in a significant percentage of the groups assessed. It now appears that, for pregnant women, supplementing with at least 300 mcg (and optimally 400 mcg) of folic acid per day is sufficient to prevent a folate deficiency, even if dietary intake is low.

Vitamin A is a fat-soluble vitamin with four major functions in the body: (1) It helps cells reproduce normally a process called differentiation (cells that have not properly differentiated are more likely to undergo pre-cancerous changes). (2) It is required for vision; vitamin A maintains healthy cells in various structures of the eye and is required for the transduction of light into nerve signals in the retina. (3) It is required for normal growth and development of the embryo and fetus, influencing genes that determine the sequential development of organs in embryonic development. (4) It may be required for normal reproductive function, with influences on the function and development of sperm, ovaries and placenta.

Liver, dairy products, and cod liver oil are good sources of vitamin A. Vitamin A is also available in supplement form.

People who limit their consumption of liver, dairy foods, and beta-carotene-containing vegetables can develop a vitamin A deficiency. Extremely low birth weight babies (2.2 pounds or less) are at high risk of being born with a deficiency, and vitamin A shots given to these infants have been reported in double-blind research to reduce the risk of lung disease. The earliest deficiency sign is poor night vision. Deficiency symptoms can also include dry skin, increased risk of infections, and metaplasia (a precancerous condition). Severe deficiencies causing blindness are extremely rare in Western societies. Less severe deficiencies are more likely to occur with a variety of conditions causing malabsorption. A high incidence of vitamin A deficiency in people infected with HIV has also been reported. People with hypothyroidism have an impaired ability to convert beta-carotene to vitamin A. For this reason, some doctors suggest taking supplemental vitamin A (perhaps 5,000–10,000 IU per day) if they are not consuming adequate amounts in their diet. Very old people with type 2 diabetes have shown a significant age-related decline in blood levels of vitamin A, irrespective of their dietary intake.

Anemia (for deficiency) Childhood diseases Cystic fibrosis Infection Leukoplakia Measles (for deficiency) Night blindness Bronchitis Celiac disease (for deficiency only) Heart attack Immune function Iron-deficiency anemia (as an adjunct to supplemental iron) Measles (for severe cases) Menorrhagia (heavy menstruation) Peptic ulcer Retinitis pigmentosa Sprains and strains (for deficiency only) Wound healing Acne Alcohol withdrawal support Conjunctivitis/blepharitis Crohn’s disease Diarrhea Gastritis Goiter HIV support Hypothyroidism Lung cancer Pap smear (abnormal) Pre- and post-surgery health Premenstrual syndrome (see dosage warnings) Retinopathy (in combination with selenium, vitamin C and vitamin E) Sickle cell anemia Urinary tract infection Vaginitis

Since a 1995 report from the New England Journal of Medicine, women who are or could become pregnant have been told by doctors to take less than 10,000 IU (3,000 mcg) per day of vitamin A to avoid the risk of birth defect. A recent report studied several hundred women exposed to 10,000–300,000 IU (median exposure of 50,000 IU) per day. Three major malformations occurred in this study, but all could have happened in the absence of vitamin A supplementation. Surprisingly, no congenital malformations happened in any of the 120 infants exposed to maternal intakes of vitamin A that exceeded 50,000 IU per day. In fact, the high-exposure group had a 50% decreased risk for malformations compared with infants not exposed to vitamin A. The authors noted that some previous studies found no link between vitamin A and birth defects, and argued the studies that did find such a link suffered from various weaknesses. A closer look at the recent study reveals a 32% higher than expected risk of birth defects in infants exposed to 10,000–40,000 IU of vitamin A per day, but paradoxically a 37% decreased risk for those exposed to even higher levels. This suggests that both “higher” and “lower” risks may have been due to chance. Excessive dietary intake of vitamin A has been associated with birth defects in humans in fewer than 20 reported cases over the past 30 years. Presently, the level at which vitamin A supplementation may cause birth defects is not known, though combined human and animal data suggest that 30,000 IU per day should be considered safe. Women who are or who could become pregnant should consult with a doctor before supplementing with more than 10,000 IU per day. Vitamin A supplements can both help and hurt children. Many people have heard that vitamin A supplements support immune function and prevent infections. This is true under some circumstances. However, vitamin A can also increase the risk of infections, according to the findings of a double-blind trial. In a study of African children between six months and five years old, a 44% reduction in the risk of severe diarrhea was seen in those children given four 100,000–200,000 IU applications of vitamin A (the lower amount for those less than a year old) during an eight-month period. On further investigation, the researchers discovered that the reduction in diarrhea occurred only in children who were very malnourished. For children who were not starving, vitamin A supplementation actually increased the risk of diarrhea compared with the placebo group. The vitamin A-supplemented children also had a 67% increased risk of coughing and rapid breathing, signs of further lung infection, although this problem did not appear in children infected with AIDS. These findings should be of concern to American parents, whose children are not usually infected with AIDS or severely malnourished. Such relatively healthy children fared poorly in the African trial in terms of both the risk of diarrhea and the risk of continued lung problems. Vitamin A provided no benefit to the well-nourished kids. Therefore, it makes sense to not give vitamin A supplements to children unless there is a special reason to do so, such as the presence of a condition causing malabsorption (e.g., celiac disease). In a study of people with retinitis pigmentosa (a degenerative condition of the eye), participants received 15,000 IU of vitamin A per day for 12 years with no signs of adverse effects or toxicity. For other adults, intake above 25,000 IU (7,500 mcg) per day can in rare cases cause headaches, dry skin, hair loss, fatigue, bone problems, and liver damage. At higher levels (for example 100,000 IU per day) these problems become more common. A controlled clinical trial showed that people who took 25,000 IU of vitamin A per day for a median of 3.8 years had an 11% increase in triglycerides, a 3% increase in total cholesterol and a 1% decrease in HDL cholesterol compared to those who did not take vitamin A. Although the significance of these findings is not clear, people at risk for cardiovascular disease should use caution when considering long-term vitamin A supplementation. One study found that increasing the intake of vitamin A in the diet was associated with bone loss and risk of hip fracture, possibly due to a vitamin A-induced stimulation of cells that break down bone. In this study, a vitamin A intake greater than 5,000 IU per day, when compared to a lower intake, was associated with a reduction in bone mineral density that approximately doubles the risk of hip fracture. Beta-carotene (which can be used by the body to make vitamin A) has not been linked to reduced bone mass. Until more is known, people concerned about osteoporosis may consider taking beta-carotene supplements rather than supplementing with vitamin A. Data from test tube, animal, and human studies show that excessive vitamin A intake can accelerate bone loss and inhibit formation of new bone, increasing the risk of osteoporosis. In humans, small studies have found these effects at about 85,000–125,000 IU per day. Taking vitamin A and iron together helps overcome iron deficiency more effectively than iron supplementation alone. Supplementation with zinc, iron, or the combination has been found to improve vitamin A status among children at high risk for deficiency of the three nutrients. Certain medicines may interact with vitamin A. Refer to drug interactions for a list of those medicines.

For most people, up to 25,000 IU (7,500 mcg) of vitamin A per day is considered safe. However, people over age 65 and those with liver disease should probably not supplement with more than 15,000 IU per day, unless supervised by a doctor. In women who could become pregnant, the maximum safe intake is being re-evaluated. However, less than 10,000 IU (3,000 mcg) per day is generally accepted as safe. There is concern that larger intakes could cause birth defects. Whether the average person would benefit from vitamin A supplementation remains unclear.

Medium-chain triglycerides are a class of fatty acids. Their chemical composition is of a shorter length than the long-chain fatty acids present in most other fats and oils, which accounts for their name. They are also different from other fats in that they have a slightly lower calorie content and they are more rapidly absorbed and burned as energy, resembling carbohydrate more than fat.

Medium-chain triglycerides are found in coconut oil, palm kernel oil, and butter. Medium-chain triglycerides are also available as a supplement.

Most people consume adequate amounts of fat in their diets and many people consume excessive amounts, so extra fat intake as medium-chain triglycerides is unnecessary.

Athletic performance Type 2 diabetes

Consuming medium-chain triglycerides on an empty stomach can lead to gastrointestinal upset. Anyone with cirrhosis or other liver problems should check with a doctor before using medium-chain triglycerides. Two reports suggest that medium-chain triglycerides may raise serum cholesterol and/or triglycerides. Medium-chain triglycerides are actually the preferred fatty acid source for cirrhotic patients, but only when used intermittently. At the time of writing, there were no well-known drug interactions with medium-chain triglycerides.

The best amount of medium-chain triglycerides to take is currently unknown. Athletes are not likely to benefit from less than 50 grams during exercise. Larger amounts may possibly help some, but may also impair performance if not combined with carbohydrate.

Glutathione is a small protein composed of three amino acids: cysteine, glutamic acid, and glycine.

Dietary glutathione is found in fresh and frozen fruits and vegetables, fish, and meat. Asparagus, avocado, and walnuts are particularly rich dietary sources of glutathione.

A deficiency can be the result of diseases that increase the need for glutathione, deficiencies of the amino acids needed for synthesis, or diseases that inhibit glutathione formation. Examples of some health conditions that are associated with glutathione deficiency include diabetes, low sperm counts, liver disease, cataracts, and HIV infection, respiratory distress syndrome, cancer, and idiopathic pulmonary fibrosis. Cigarette smoking is also associated with low glutathione levels because it increases the rate of utilization of glutathione.

Colon cancer

No side effects or interactions are known with oral administration of glutathione. Certain medicines may interact with glutathione. Refer to drug interactions for a list of those medicines.

There is very little evidence that taking glutathione supplements provides any benefit, despite promising evidence about the effects of aerosol, intravenous, and intramuscular glutathione, for people with a wide variety of conditions. People who have a proven glutathione deficiency, which may require administration of glutathione intravenously, intramuscularly, or by aerosol, should be treated by a healthcare professional. All ovarian cancer patients currently taking cisplatin (Platinol®) should discuss using intravenous glutathione with a healthcare professional.

Proanthocyanidins also called “OPCs” for oligomeric procyanidins or “PCOs” for procyanidolic oligomers are a class of nutrients belonging to the flavonoid family.

Proanthocyanidins can be found in many plants, most notably pine bark, grape seed, and grape skin. However, bilberry, cranberry, black currant, green tea, black tea, and other plants also contain these flavonoids. Nutritional supplements containing proanthocyanidins extracts from various plant sources are available, alone or in combination with other nutrients, in herbal extracts, capsules, and tablets.

Flavonoids and proanthocyanidins are not classified as essential nutrients because their absence does not induce a deficiency state. However, proanthocyanidins may have many health benefits, and anyone not eating the various plants that contain them would not derive these benefits.

Chronic venous insufficiency Capillary fragility Retinopathy Sunburn Pancreatic insufficiency Varicose Veins

Flavonoids, in general, and proanthocyanidins, specifically, have not been associated with any consistent side effects. As they are water-soluble nutrients, excess intake is simply excreted in the urine. At the time of writing, there were no well-known drug interactions with Proanthocyanidins.

Flavonoids (proanthocyanidins and others) are a significant source of antioxidants in the average diet. Proanthocyanidins at 50–100 mg per day is considered a reasonable supplemental level by some doctors, but optimal levels remain unknown.

Inosine is a nucleoside, one of the basic compounds comprising cells. It is a precursor to adenosine, an important energy molecule, and plays many supportive roles in the body.

Inosine is found in brewer’s yeast and organ meats. It is also available as a supplement.

Inosine is not an essential nutrient, so deficiencies do not occur.

Multiple Sclerosis

No side effects have been reported with the use of inosine for two to five days in the limited research available. However, unused inosine is converted by the body to uric acid, which may be hazardous to people at risk for gout. At the time of writing, there were no well-known drug interactions with inosine.

Although a common amount of inosine taken by athletes is 5,000–6,000 mg per day, little scientific evidence supports the use of this supplement in any amount.

Chondroitin sulfate consists of repeating chains of molecules called glycosaminoglycans (GAGs). Chondroitin sulfate is a major constituent of cartilage, providing structure, holding water and nutrients, and allowing other molecules to move through cartilage an important property, as there is no blood supply to cartilage.

The only significant food source of chondroitin sulfate is animal cartilage.

Because the body makes chondroitin, the possibility of a dietary deficiency remains uncertain. Nevertheless, chondroitin sulfate may be reduced in joint cartilage affected by osteoarthritis and possibly other forms of arthritis.

Osteoarthritis Wound healing (topical) Atherosclerosis Heart attack High cholesterol Kidney stones Sprains and strains Wound healing (oral)

Nausea may occur at intakes greater than 10 grams per day. No other adverse effects have been reported. One doctor has raised a concern that chondroitin sulfate should not be used by men with prostate cancer. This concern is based upon two studies. In one, the concentration of chondroitin sulfate was found to be higher in cancerous prostate tissue as compared to normal prostate tissue. In the other study, it was shown that higher concentrations of chondroitin sulfate in the tissue surrounding a cancerous prostate tumor predict a higher rate of recurrence of the cancer after surgery. However, no studies to date have addressed the question of whether taking chondroitin sulfate supplements could promote the development of prostate cancer. Simply because a substance is present in or around cancerous tissue does not by itself suggest that that substance is causing the cancer. For example, calcium is a component of atherosclerotic plaques that harden the arteries; however, there is no evidence that taking calcium supplements causes atherosclerosis. To provide meaningful information, further studies would need to track the incidence of prostate cancer in men taking chondroitin supplements. Until then, most nutritionally-oriented doctors remain unconcerned about this issue. It is not known whether taking glucosamine sulfate and chondroitin sulfate in combination is a more effective treatment for osteoarthritis than taking either one by itself. At the time of writing, there were no well-known drug interactions with chondroitin sulfate.

For atherosclerosis, researchers have sometimes started therapy using very high amounts, such as 5 grams twice per day with meals, lowering the amount to 500 mg three times per day after a few months. Before taking such high amounts, people should consult a doctor. For osteoarthritis, a typical level is 400 mg three times per day. Oral chondroitin sulfate is rapidly absorbed in humans when it is dissolved in water prior to ingestion. Approximately 12% of chondroitin sulfate taken by mouth becomes available to the joint tissues from the blood.