What It Is and How it Works?
Vitamin B6 is a water-soluble vitamin that exists in three major chemical forms: pyridoxine, pyridoxal and pyridoxamine. It performs a wide variety of functions in your body and is essential for your good health. For example, vitamin B6 is needed for more than 100 enzymes involved in protein metabolism. It also is essential for red blood cell metabolism. The nervous and immune systems need vitamin B6 to function efficiently, and it also is needed for the conversion of tryptophan (an amino acid) to niacin (a vitamin).
Hemoglobin within red blood cells carries oxygen to tissues. Your body needs vitamin B6 to make hemoglobin. Vitamin B6 also helps increase the amount of oxygen carried by hemoglobin. A vitamin B6 deficiency can result in a form of anemia that is similar to iron deficiency anemia.
An immune response is a broad term that describes a variety of biochemical changes that occur in an effort to fight off infections. Calories, protein, vitamins and minerals are important to your immune defenses because they promote the growth of white blood cells that directly fight infections. Vitamin B6, through its involvement in protein metabolism and cellular growth, is important to the immune system. It helps maintain the health of lymphoid organs (thymus, spleen and lymph nodes) that make your white blood cells. Animal studies show that a vitamin B6 deficiency can decrease your antibody production and suppress your immune response.
Vitamin B6 also helps maintain your blood glucose (sugar) within a normal range. When caloric intake is low, your body needs vitamin B6 to help convert stored carbohydrate or other nutrients to glucose to maintain normal blood sugar levels. While a shortage of vitamin B6 will limit these functions, supplements of this vitamin do not enhance them in well-nourished individuals.
Vitamin B6 can help with weight loss through a stimulating effect of the thyroid. This can be especially helpful for hormone balance in women when water retention is an issue. Lastly, patients seem to find the pyridoxine alleviates cravings consistently. Vitamin B6 is found in a wide variety of foods, including fortified cereals, beans, meat, poultry, fish, and some fruits and vegetables. The table of selected food sources of vitamin B6 suggests many dietary sources of B6.
The Recommended Dietary Allowance (RDA) is the average daily dietary intake level that is sufficient to meet the nutrient requirements of nearly all (97 percent to 98 percent) healthy individuals in each life-stage and gender group. The 1998 RDAs for vitamin B6 for adults, in milligrams, are 1.3 mg for men and women ages 9-50 and 1.7 mg and 1.5 mg for men and women over the age of 51, respectively.
Clinical signs of vitamin B6 deficiency are rarely seen in the United States. Many older Americans, however, have low blood levels of vitamin B6, which may suggest a marginal or sub-optimal vitamin B6 nutritional status. Vitamin B6 deficiency can occur in individuals with poor quality diets that are deficient in many nutrients. Symptoms occur during later stages of deficiency, when intake has been very low for an extended time. Signs of vitamin B6 deficiency include dermatitis (skin inflammation), glossitis (a sore tongue), depression, confusion and convulsions. Vitamin B6 deficiency also can cause anemia. Some of these symptoms also can result from a variety of medical conditions other than vitamin B6 deficiency. It is important to have a physician evaluate these symptoms so that appropriate medical care can be given.
The Relationship Between B6 and heart disease
A deficiency of vitamin B6, folic acid or vitamin B12 may increase your level of homocysteine, an amino acid normally found in your blood . There is evidence that an elevated homocysteine level is an independent risk factor for heart disease and stroke. The evidence suggests that high levels of homocysteine may damage coronary arteries or make it easier for blood clotting cells called platelets to clump together and form a clot. However, there is currently no evidence available to suggest that lowering homocysteine level with vitamins will reduce your risk of heart disease. Clinical intervention trials are needed to determine whether supplementation with vitamin B6, folic acid or vitamin B12 can help protect you against developing coronary heart disease.
Concerns and Other Issues Associated with B6
Too much vitamin B6 can result in nerve damage to the arms and legs. This neuropathy is usually related to high intake of vitamin B6 from supplements and is reversible when supplementation is stopped. According to the Institute of Medicine, “Several reports show sensory neuropathy at doses lower than 500 mg per day”. As previously mentioned, the Food and Nutrition Board of the IOM has established an Upper Tolerable Intake Level (UL) for vitamin B6 of 100 mg per day for all adults. “As intake increases above the UL, the risk of adverse effects increases.”
Vitamin B6 is needed for the synthesis of neurotransmitters, such as serotonin and dopamine. These neurotransmitters are required for normal nerve cell communication. Researchers have been investigating the relationship between vitamin B6 status and a wide variety of neurologic conditions, such as seizures, chronic pain, depression, headache and Parkinson’s disease.
Lower levels of serotonin have been found in individuals suffering from depression and migraine headaches. So far, however, vitamin B6 supplements have not proved effective for relieving these symptoms. One study found that a sugar pill was just as likely as vitamin B6 to relieve headaches and depression associated with low dose oral contraceptives.
Alcohol abuse can result in neuropathy, abnormal nerve sensations in the arms and legs. A poor dietary intake contributes to this neuropathy and dietary supplements that include vitamin B6 may prevent or decrease its incidence.
There are many drugs that interfere with the metabolism of vitamin B6. Isoniazid, which is used to treat tuberculosis, and L-DOPA, which is used to treat a variety of neurologic problems such as Parkinson’s disease, alter the activity of vitamin B6. There is disagreement about the need for routine vitamin B6 supplementation when taking isoniazid. Acute isoniazid toxicity can result in coma and seizures that are reversed by vitamin B6, but in a group of children receiving isoniazid, no cases of neurological or neuropsychiatric problems were observed regardless of whether or not they took a vitamin B6 supplement. Some doctors recommend taking a supplement that provides 100 percent of the RDA for B6, which is usually enough to prevent symptoms of vitamin B6 deficiency, when isoniazid is prescribed. It is important to consult with a physician about the need for a vitamin B6 supplement when taking isoniazid.
B12 and B6 Injections in Weight Management
One of the key proponents of the use of B6 and B12 injections in a weight loss regiment is Dr. Stanley Bernstein. Dr. Bernstein has been running his weight loss clinics for 25 years, mainly in Ontario. The diet that bears his name is a unique program that includes injections and does not require exercise.
Bernstein says his diet is 100 per cent medically supervised and it’s about more than just counting calories. “We use a lot of vitamins and minerals on our patients and we have a unique feature. Some of our vitamins are given by injection.” Clients are injected with a combination of Vitamin B6 and B12, three times a week. The idea is that the vitamins work to break down the fat. “The B vitamins make it easy for someone to stay on a diet,” Bernstein said. “I find that they enhance the weight loss. Our patients are losing between four and five pounds a week.” But rapid weight loss can be costly. The initial consultation ranges from $195 to $235. Add to that $100 per week for services and injections. Bernstein says an average patient who loses about 35 pounds will wind up paying about $1,000.
Interestingly, Bernstein admits “there is not specific literature that will tell you that B vitamins are going to burn off fat, ….. but there are a lot of articles about B vitamins being important for metabolizing food.” (https://www.cbc.ca/consumers/market/files/health/bernstein_diet/)
Harvard nutrition expert Dr. George Blackburn says the injections are like an electrical stimulus: “It’s something to remind you that you’re on this program and you want to be compliant to it. It’s used as a motivator to make people adhere to the diet, in this case.”
Equally, Dr. Kent Sharian suggests that, “If you get a patient to come to the office three times a week to be weighed, checked and have to be accountable for his weight, chances are that he or she will make an extra effort to show a weight loss. That has nothing to do with the injections that act primarily as a placebo to get the patient into the office.”
Jeff Russell, the program director at Glenmore Healthcare, a leading Calgary weight loss clinic, says “We find the addition of B6 and B-Complex certainly helps patients who are on our VLCD (Very Low Caloric Intake) Clean Start Weight Loss program.”
FDA and other Professional Concerns
The American Society of Bariatric Physicians’ position is that B12 injections are “no help with weight loss; there is no evidence that they work.” The FDA has a consumer website aimed at helping consumers understand vitamins and what they can and cannot achieve.
What It Is and How it Works?
Vitamin B12, also called cobalamin, is important to good health. As well, there are links to B12 and weight loss. It helps maintain healthy nerve cells and red blood cells, and also is needed to make DNA, the genetic material in all cells. Vitamin B12 is bound to the protein in food. Hydrochloric acid in the stomach releases B12 from protein during digestion. Once released, B12 combines with a substance called intrinsic factor (IF) before it is absorbed into the bloodstream.
All of these B vitamins help the body in converting carbohydrates into glucose or sugar, which is burned in order to produce energy for proper body function. These are often referred to as B complex vitamins, and are essential for the breakdown of fats and proteins. They help maintain muscle tone, protect the mucus lining in the digestive tract and mouth, and promote upkeep of nervous system and the organs like the liver, skin, hair, and eyes. Cobalamine is an excellent anti-stress vitamin since it is believed to enhance the health functioning of the immune system and improve the body’s ability to fight stressful conditions.
B12 injections have been found to frequently improve energy levels and general well-being. They also support thyroid function to regulate energy levels. B12 also reduces water retention owing to its diuretic attributes. Vitamin B12 is naturally found in animal foods, including fish, milk and milk products, eggs, meat and poultry. Fortified breakfast cereals are an excellent source of vitamin B12 and a particularly valuable source for vegetarians. The table of selected food sources of vitamin B12 suggests dietary sources of vitamin B12.
The Recommended Dietary Allowance (RDA) is the average daily dietary intake level that is sufficient to meet the nutrient requirements of nearly all (97 percent to 98 percent) healthy individuals in each life-stage and gender group. The 1998 RDAs for vitamin B12 (in micrograms) for adults are 2.4 µg and the results of two national surveys, the National Health and Nutrition Examination Survey (NHANES III-1988-91) and the Continuing Survey of Food Intakes by Individuals (CSFII 1994-96) found that most adult men and women consume recommended amounts of vitamin B12.
Diets of most adult Americans provide recommended intakes of vitamin B12, but deficiency may still occur as a result of an inability to absorb B12 from food. It also can occur in individuals with dietary patterns that exclude animal or fortified foods. As a general rule, most individuals who develop a vitamin B12 deficiency have an underlying stomach or intestinal disorder that limits the absorption of vitamin B12. Sometimes the only symptom of these intestinal disorders is anemia resulting from B12 deficiency.
Characteristic signs of B12 deficiency include fatigue, weakness, nausea, constipation, flatulence (gas), loss of appetite and weight loss. Deficiency also can lead to neurological changes such as numbness and tingling in the hands and feet. Additional symptoms of B12 deficiency are difficulty in maintaining balance, depression, confusion, poor memory, and soreness of the mouth or tongue. Some of these symptoms also can result from a variety of medical conditions other than vitamin B12 deficiency. It is important to have a physician evaluate these symptoms so that appropriate medical care can be given.
Surgical procedures of the gastrointestinal tract such as surgery to remove all or part of the stomach often result in a loss of cells that secrete stomach acid and intrinsic factor. Surgical removal of the distal ileum, a section of the intestines, also can result in the inability to absorb B12. Anyone who has had either of these surgeries usually requires lifelong supplemental B12 to prevent a deficiency.
The Relationship Between Vitamin B12 and Heart Disease?
A deficiency of vitamin B12, folate or vitamin B6 may increase your blood level of homocysteine, an amino acid normally found in your blood. There is evidence that an elevated blood level of homocysteine is an independent risk factor for heart disease and stroke. The evidence suggests that high levels of homocysteine may damage coronary arteries or make it easier for blood-clotting cells called platelets to clump together and form a clot. However, there is currently no evidence available to suggest that lowering homocysteine level with vitamins will actually reduce your risk of heart disease. Clinical intervention trials are needed to determine whether supplementation with vitamin B12, folic acid or vitamin B6 can help protect against developing coronary heart disease.
Vitamin B12 has a very low potential for toxicity. The Institute of Medicine states “no adverse effects have been associated with excess vitamin B12 intake from food and supplements in healthy individuals.” The Institute recommends that adults older than 50 years of age get most of their vitamin B12 from supplements or fortified food because of the high incidence of impaired absorption of B12 from unfortified foods in this population.