The Recommended Dietary Allowances for Bodybuilders (RDA-B)

by Rehan Jalali

Rehan is the author of the book, Six-Pack Diet Plan. "Six-pack" abdominal muscles have long been viewed as the sign of ultimate physical fitness. Although many people strive for this level of fitness, lasting success evades them. Bodybuilders, advertising models, and professional athletes make achieving a "washboard" stomach look easy. So why do so many people have trouble getting lean abs and lowering their body fat? Can you get six-pack abs and maintain this level of fitness permanently? Sure you can. When you realize that there's no "magical" solution for losing excess weight and that quick fixes and short-term diets just won't work on a long-term basis, you'll be ready for "The Six-Pack Diet Plan."

The RDA (recommended dietary allowance) is a guideline designed for the maintenance of good nutrition of practically all healthy people in the U.S. It gives a certain amount of various nutrients which is a bare minimum to help prevent disease. This is O.K. for the normal person but what about bodybuilders? This minimum amount of nutrients will not be enough for bodybuilders who put their bodies through stress in intensive training. These athletes would need more of certain nutrients to help them in their training as well as allow them to prevent a disease condition. Certain recommendations are different for bodybuilders. What if there was another general guideline for minimum nutrient intake for bodybuilders? With that, I now propose the RDAB (recommended dietary allowances for bodybuilders)! Certain research shows that athletes need higher quantities of nutrients to maintain proper bodily function and to improve their athletic performance (1). Some key nutrients will be discussed and compared to the RDA. The new RDAB will be established based on a bodybuilder's needs.

Let's start with protein. Proteins break down to amino acids which are essential to muscle growth and function. The RDA for protein for males is about 56 grams daily. Bodybuilders need more protein to allow them to recover from the catabolic states they create in their bodies after an intense training session. Extra protein is also needed to allow bodybuilders to gain lean muscle mass (which is the goal of virtually all bodybuilders including myself). I would say that the RDAB for protein would be 1 gram of protein per pound of bodyweight in divided amounts throughout the day.

Vitamin C or ascorbic acid is an essential water soluble vitamin for any intensely training athletes including bodybuilders. It has several functions including anti-oxidant properties, collagen synthesis (2), immuno-enhancing effects, and decreasing cortisol levels. According to Dr. Linus Pauling, who is probably one of the greatest researchers of Vitamin C, most animals, except humans, monkeys and apes can produce Vitamin C endogenously without taking it in from foods. These animals make Vitamin C in their liver in amounts that are proportional to their respected bodyweights. This turns to out to be an average of about 10-12 grams of vitamin C a day for a normal adult. Now for all you biochemistry wannabe's, the reason why humans need exogenous sources of vitamin C is because they lack an enzyme called gulunolactone oxidase, which is the last enzyme needed for ascorbic acid synthesis (3). Vitamin C helps fight free radicals in the body. Free radicals are responsible for all kinds of oxidative damage in the body. Vitamin C has been shown to considerably decrease the duration of cold episodes and the severity of symptoms(4). If your sick, you cannot train properly and you may lose hard earned muscle. Vitamin C also has shown to increase the testosterone:cortisol ratio by decreasing cortisol levels (2). Cortisol is a catabolic hormone that is secreted in times of stress including strenuous weight training. Vitamin C also aids in collagen synthesis. Collagen is a very important substance in the human body. It strengthens the skin, muscles, and bones. Collagen is a primary component of ligaments and tendons. There are many studies that document vitamin C's importance for healthy ligaments and tendons (2,5). Vitamin C is required in a reaction that stimulates collagen formation (3). Bodybuilders need to have healthy joints to allow them to train properly. This is especially true for bodybuilders who have been training for many years. Vitamin C is also important in the synthesis of carnitine. Sufficient production of carnitine is important in fat metabolism because carnitine helps transport long chain fatty acids into the mitochondria for their breakdown to occur. Vitamin C also plays a key role in neurotransmitter synthesis and cholesterol catabolism (3). There doesn't seem to be a superior form of Vitamin C on the market so plain old ascorbic acid is just fine (6). I would not however recommend the timed release version since it may cause kidney remnants to accumulate. Some food sources of vitamin C are orange juice, papaya, cantaloupe, and broccoli. So overall, Vitamin C is a very essential vitamin for bodybuilders. I would suggest the RDAB for Vitamin C be 6 grams daily. This is about 100 times the regular RDA for adults. A 2 gram dosage before weight training may be beneficial because it may decrease post-workout inflammation.

Vitamin A is used to refer to retinol and retinal. Retinoic acid is a by-product of retinal. Provitamin A refers to beta-carotene which can be converted to retinol in the body. The roles of Vitamin A include the visual cycle, cellular differentiation (affects gene expression to control cell development), growth (stimulates the growth of epithelial cells and appears to increase the number of specific receptors for growth factors[7]), reproductive processes in males and females, bone development, and proper immune function. Vitamin A works with both zinc and vitamins K and E. A deficiency of these nutrients may impair the function of Vitamin A. Food sources of vitamin A include beef liver, sweet potatoes, carrots, and spinach. A lot of the functions of Vitamin A are important to bodybuilders so the RDAB is set at 30,000 I.U. daily.

Vitamin D is associated with skeletal growth and strong bones. Calcitriol, 1,25 -(OH)2 D3, is considered the active form of Vitamin D and functions like a steroid hormone. Calcitriol plays a key role in parathyroid hormone which directs the homeostasis of blood calcium concentrations. Parathyroid hormone also stimulates calcium and phosphorous reabsorption in the distal renal tubule of the kidneys (8). When normal humans are exposed to sunlight, the body can produce it's own Vitamin D. Vitamin D may also help delay arthritis which is sometimes found in long term bodybuilders. Some food sources of vitamin D include sunlight and fortified milk. The RDAB in sunny climates is 500 IU of vitamin D daily and 700 IU in cloudy or sun-less climates.

Vitamin E includes eight different compounds synthesized by plants. Vitamin E activity is greatest in alpha-tocopherol or more specifically d-alpha tocopherol. It is a fat soluble vitamin. The main function of vitamin E is to maintain membrane integrity in body cells as it may provide physical stability to membranes (9). It acts as a powerful anti-oxidant preventing the oxidation (peroxidation) of unsaturated fatty acids in the phospholipids of cellular membranes. Vitamin E helps fight free radicals. There is an interrelationship between vitamin E and selenium because both of these nutrients at tied closely in the function of glutathione peroxidase (a very powerful antioxidant in the body). Vitamin E can be regenerated with the help of Vitamin C. A good food source of this vitamin is vegetable seed oil. The RDAB is set at 800 IU daily. High intakes of Vitamin E can interfere with the functions of other fat soluble vitamins (8) so I would not recommend taking excess amounts.

Vitamin K is a fat soluble vitamin which plays an integral part in blood coagulation. It actually may strengthen the bone matrix (10). Food sources include green leafy vegetables and soy beans. I do not think excess vitamin K will help bodybuilders but a deficiency should be avoided by consuming the RDAB for vitamin K of 100 mcg daily.

Thiamin (vitamin B1) is primarily in the form of thiamin monophosphate (TMP) in the blood. Thiamin can also be converted to it's phosphorylated form, thiamin diphosphate (TDP) in the body. TDP functions as a coenzyme which is necessary for the oxidative decarboxylation of both pyruvate and alpha-ketoglutarate. This is essential for generating ATP (energy). This would definitely be important in promoting muscle function. Thiamin is also important in nerve conduction. It appears to mimic and potentiate the effects of acetylcholine which is a neurotransmitter involved in memory (11). Coffee may inhibit the effects of thiamin so I would not recommend taking thiamin with coffee. Some food sources of this vitamin include yeast, sunflower seeds, and legumes. The RDAB for thiamin is established at 60mg daily. Water soluble vitamins rarely show any toxicity because excess water soluble vitamins are excreted in the urine.

Riboflavin (vitamin B2) has two coenzyme forms : flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD). These coenzymes function in many metabolic reactions in the body. They can act as oxidizing agents because of their ability to accept a pair of hydrogen atoms. It is a part of choline metabolism. In fact, other neurotransmitters such as dopamine require FAD for their metabolism. This can stimulate energy levels during exercise for bodybuilders since dopamine can convert to epinephrine and norepinephrine. Foods that have a good amount of riboflavin include beef liver, lean sirloin steak, mushrooms, and ricotta cheese. The RDAB for riboflavin is set at 25mg daily.

Niacin (vitamin B3) is also termed nicotinic acid and nicotinamide. Meats provide niacin as free nicotinamide(12). Niacin can occur as two nucleotides: NAD and NADP. It can also be formed in the liver from the amino acid tryptophan. There are about 200 enzyme which require NAD And NADP. NAD helps produce ATP(energy). NADPH is used in a variety of processes including fatty acid synthesis, cholesterol and steroid hormone synthesis, oxidation of glutamate, and it may help reduce the oxidized form of vitamin C, dehydroascorbate. Niacin has also been shown to decrease cholesterol levels. It does cause a flush ( redness and vasodilation) especially when taken on an empty stomach. Very high doses of niacin may also be hard on the liver. Some bodybuilders use it to increase vascularity along with yohimbe. Since it acts as a vasodilator, it does work pretty well to increase vascularity in many bodybuilders. It may also increase energy during a workout. In fact, I have taken between 300-400 mg before a workout and had excellent results. If you have problems with the liver or the "niacin flush", you may want to try the inositol hexonicotinate form which is easier on the liver and doesn't cause the dreaded flush. Food sources of niacin include tuna, chicken breast, and beef. Due to the importance of this vitamin for bodybuilders, the RDAB of niacin is set at 200mg daily.

Pantothenic acid (vitamin B5) is abundantly found in foods. It is a vital component of Coenzyme A(CoA) and is actually used, along with cysteine and ATP, to form Coenzyme A. Pantothenic acid, as a component of coenzyme A is essential for production of energy from carbohydrates, fat, and protein. So basically, pantothenic acid plays an important role in energy storage as well as energy release. Some studies suggest it may also accelerate the healing process after surgery(13). Pantothenic acid is abundant in many foods including egg yolk and yeast. Due to it's role in energy function, the RDAB for pantothenic acid is set at 8 mg daily.

Pyridoxine (vitamin B6) comes in several forms. Heating, canning, freezing , or processing foods can decrease the amount of Vitamin B6 in foods. The coenzyme form of this vitamin is associated with a vast number of enzymes, the majority of these enzymes are a part of amino acid metabolism. Vitamin B6 is also necessary to synthesize heme. Niacin synthesis from tryptophan requires PLP (pyridoxal phosphate) , which is one of the forms of vitamin B6. It is necessary in glycogen catabolism to "unlock" carbohydrate energy. Vitamin B6 has also been shown to diminish the actions of certain steroids such as glucocorticoid hormones (cortisol [14]). Bodybuilders definitely want to decrease their cortisol level to allow for proper lean muscle mass gains and to prevent the symptoms of overtraining. Food sources of Vitamin B6 include sirloin steak, navy beans, and potato. Since it has many important functions relative to bodybuilders, the RDAB for Vitamin B6 is set at 25 mg. daily.

Folic acid (folate) is a vitamin found in green vegetables and mushrooms. It is very easily destroyed by light and heat. This may cause folate deficiencies for many people. Folate is necessary in amino acid metabolism especially with serine and methionine. It is also required for histidine metabolism. Deficiencies in this vitamin can cause muscle weakness. Ascorbic acid helps to protect folate from oxidative destruction. There is a synergistic relationship between folate and vitamin B12 (cobalamin). This relationship is sometimes called the "methyl-folate trap" because without vitamin B12 the folate is rendered useless in the body. Food sources include mushrooms, spinach, and broccoli. Again, I don't think taking excessive dosages will help bodybuilders but deficiencies can cause a lot of negative effects that bodybuilders definitely want to avoid. The RDAB for folic acid is set at 3 mg.

Biotin was once referred to as Vitamin H. Egg yolks contain a high amount of biotin. Egg whites contain a protein called avidin which is unstable in heat. It actually binds biotin inhibiting it's absorption. That is why it is very important to cook egg whites. Biotin helps many enzymes function in the body. It helps in energy metabolism and is important in the utilization of fats and amino acids in the body. The RDAB for biotin is set at 400mcg for preventing any deficiencies.

Vitamin B12 (cobalamins) are usually found only in animal products. Some bodybuilders say it increases their energy levels but I have not found this to be true. A deficiency can cause anemia to occur. Meat, fish, and poultry are good food sources of vitamin B12. The RDAB for vitamin B12 is set at 20 mcg daily.

Calcium is the most abundant mineral in the body. It is considered a macromineral because of it's abundance. It is essential to the structural matrix of bones and teeth. In fact, about 99% of total body calcium is found in the bones and teeth (3). Calcium has various other functions such as blood clotting, nerve conduction, muscle contraction, enzyme regulation, and membrane permeability (15). Only the ionized form of calcium is active and helps perform these functions (Ca+2). Calcium has also been shown to lower blood pressure (16). Calcium binds to certain proteins such as troponin C which permits an interaction between actin and myosin (muscle proteins), resulting in muscle contraction. Since bodybuilders need to fully contract muscles, calcium is an important nutrient. Increased potassium and phosphorous consumption may also reduce urinary calcium excretion (17). One recent study actually showed that using calcium supplements (500-2000mg/daily) actually increased lean body mass and bone mineral density in male athletes (18).Calcium citrate seems to be the most absorbable form of calcium on the market. Milk and milk products contain good amounts of calcium. The RDAB for calcium is going to be set at 1400 mg/daily.

Phosphorous is second only to calcium in terms of inorganic elements in the body. Approximately 85% of phosphorous is in the skeleton. Most phosphorous is absorbed in the body in it's inorganic phosphate form. Phosphate is important in the development of skeletal tissue. Phosphorous is extremely important in the metabolism of energy nutrients, contributing to metabolic rate in the form of high energy phosphate bonds such as ATP (your body's main energy source). Phosphate is also a component of the nucleic acids DNA and RNA, functions in cell membranes as phospholipids, and is involved in acid-base balance. It may act as buffer, reducing lactic acid build up. If you can delay or decrease lactic acid build-up, you may be able to train longer and not fatigue as quickly. Studies have shown that supplementing phosphate increases endurance (19,20). Phosphate may also play a role in the formation of phophocreatine which can donate it's phosphate to ADP (adenosine di-phosphate) to help support the reproduction of ATP( adenosine tri-phosphate) . Meat, fish, eggs, and poultry are all good sources of phosphorous. Bodybuilders can definitely benefit from this supplement by taking at least 1200 mg daily. It is found in almost all foods.

Magnesium in the human body ranks fourth in overall abundance, but intracellularly it is second only to potassium. This mineral is involved in over 300 enzymatic reactions in the body (21) including glycolysis, krebs cycle, creatine phosphate formation, nucleic acid synthesis, amino acid activation, cardiac and smooth muscle contractability, cyclic AMP formation, and most importantly for bodybuilders protein synthesis. Dietary fiber impairs magnesium absorption to a small extent (22) so I would recommend that you not take magnesium with any fiber source. One study showed that subjects taking magnesium supplementation showed increases in absolute strength and lean body mass after seven weeks (23). People who sustain heart attacks are usually magnesium deficient. Food sources of magnesium include nuts, legumes, and soybeans. Since bodybuilders can benefit from magnesium I would set the RDAB at 600mg. daily. This dose is 250mg higher than the regular RDA.

Sodium has a lot to do with water balance in the body. Sodium constitutes about 93% of the cations in the blood. It helps facilitate active cellular transport across all cellular membranes via the sodium/potassium ATPase pump. The human body generally requires around 500mg. daily. Excess sodium intake can cause water retention in the intercellular space giving you a bloated and smooth appearance. That is why it is important to monitor sodium intake and not take too much. The major source of sodium in the diet is generally in the form of sodium chloride. Sodium comprises 39% by weight of sodium chloride (3). Bodybuilders need to be aware of limiting high sodium foods such as canned meats, processed foods, breads, and certain cereals. It is not advisable to completely restrict sodium intake because the hormone aldosterone is released at this time and may cause reabsorption of sodium in the nephron of the kidneys. This will decrease sodium excretion and thus cause you to hold water. This reabsorption generally takes about 24 hours so I would recommend consuming 800 mg of sodium the last two weeks before a show and then severely restrict sodium only about 18 hours before the show. Table salt, breads, cheese, and sea food are all high in sodium. The RDAB for sodium is set between 600-1000mg. daily.

Potassium is a macromineral which plays an important role in the contractile functions of smooth, cardiac, and skeletal muscle. It also affects the excitably of nerve tissue, and is important in maintaining electrolyte and PH balance. It is also part of the sodium/potassium ATPase pump which helps transport nutrients across cellular membranes. A ratio of 4:1 should be maintained between potassium and sodium to prevent certain disorders and to optimize bodily functions involving these two nutrients. Some bodybuilders take prescription diuretics such as lasix or aldactone which deplete potassium and cause muscle cramping to occur. Potassium can aid in decreasing or preventing muscle cramps especially with the use of diuretics. Food sources include bananas, oranges, peaches, and potatoes. Since bodybuilders definitely want to decrease any cramping and help in muscle contractility, The RDAB for potassium is established at 2400-400mg. daily.

Chloride is the most abundant anion in the extracellular fluid. It is important in electrolyte balance because it's negative charge neutralizes the positive charge of sodium ions with which it is usually associated. It is also required in the formation of gastric hydrochloric acid. There are no studies suggesting that it may directly increase lean muscle mass so I do not think it is of vital importance for bodybuilders to take excessive doses. Seafood and milk contain a good amount of chloride. The RDAB is set at 1800mg daily.

Iron is a micromineral which is of vital importance to the human body. The only two states of iron that are stable in the human body and in food are the ferric (Fe+3) and the ferrous (Fe+2) forms. There are two forms of iron in food, heme and non-heme. Heme iron is mainly found in beef, fish, and poultry (24). Non-heme iron is found in plant foods such as nuts, fruits , and vegetables. It is also found in milk and eggs. The difference is that non-heme iron is usually bound to components of food and must be hydrolyzed prior to absorption. Heme iron is more easily absorbed than non-heme iron. Iron is an essential component of hemoglobin and myoglobin which transport oxygen to all the cells of the body. They also help transport carbon dioxide back to the lungs where it can be expelled. Iron also helps the transport of electrons through the respiratory chain through cytochromes. A deficiency of iron may lead to anemia or a decrease in red blood cells or hemoglobin. Ascorbic acid has been shown to enhance iron absorption and maintain iron in the appropriate state for enzyme function (25). Taking 1 gram of ascorbic acid (vitamin c) with iron may increase it's absorption (especially non-heme iron). Red meats, clams, and oysters are good food sources of iron. Women tend to be more prone to anemia than males so the RDAB for women would be 30 mg. of iron daily. For male bodybuilders, the RDAB would be 25mg daily.

Zinc is found in all organs and tissues in the human body. As a component of metalloenzymes, it provides structural integrity to proteins. Zinc is a part of more enzyme systems then the rest of the microminerals combined. It affects many fundamental processes of life (26).

It is involved in gene expression, cell replication, membrane stabilization, and plays a structural role in many hormones such as insulin, testosterone, growth hormone, and estrogen. Zinc has also been shown to reduce the size of the prostrate (27). Zinc deficiency may cause an increased susceptibility to infection and certain skin disorders. Zinc may also act as an anti-oxidant thus supporting immune function (28). Zinc also helps Vitamin A function in the body. Oysters, beef liver, and wheat germ are all good food sources of zinc. I hope the necessity of Zinc has been established, especially for bodybuilders. I propose the RDAB to be 40mg daily.

Copper is an enzyme activator in crucial reactions such as the anti-inflammatory process and the biosynthesis of connective tissue. Copper status strongly affects the levels of neuropeptides, enkephalins, and endorphins (29). There is an antagonistic relationship between copper and zinc. So in other words , they compete and work against each other. This is why I would recommend you not take copper along with zinc but rather at different times of the day with food. Good food sources of copper include liver, shellfish, and whole grains. I do not think extra amounts of this vitamin are beneficial to bodybuilders but a deficiency can lead to problems. The RDAB is then established at 4 mg daily.

Selenium is an essential cofactor of glutathione peroxidase (a very powerful antioxidant enzyme). It is also involved in the cytochrome p450 system, pancreatic function, immune system function (30), DNA repair and enzyme activation, and detoxification of heavy metals. Selenium is also necessary for iodine metabolism. It acts in the conversion of thyroid hormone from thyroxine (T4) to tri-iodothyronine (T3) in the liver. T3 is the active form of thyroid in the body. Bodybuilders need to stimulate thyroid output to cause fat loss to occur. Some bodybuilders use thyroid medications such as synthroid or cytomel to stimulate thyroid output during a dieting phase. Selenium may also act as an insulin mimicker (31). Some food sources of selenium include grains, meat ,and poultry. Due to these functions, I believe bodybuilders need more than the RDA recommendation for selenium which is 70 mcg/daily. Thus the RDAB is set at 200mcg of selenium daily.

Chromium acts to help insulin function by helping to form glucose tolerance factor which helps insulin bind to it's receptor. This action will affect cellular glucose uptake and intracellular carbohydrate and lipid metabolism. Chromium may play a role in lipid metabolism by affecting lipoprotein lipase activity which may also affect cholesterol metabolism (32). RNA synthesis in vitro as directed by DNA is enhanced by chromium as well. Chromium may help reduce insulin resistance so I believe a deficiency should be avoided by bodybuilders. Some studies show it improves blood lipid profiles and causes fat loss (33). Food sources of chromium include cinnamon, brewer's yeast, and mushrooms. Due to all these factors, the RDAB is set at 400mcg. of chromium daily.

Iodide's main function is in the synthesis of the thyroid hormones by the thyroid gland. Thyroid hormones stimulate the basal rate of metabolism, oxygen consumption, and heat production. A deficiency may cause an enlargement of the thyroid gland causing a condition called goiter. Seafood, sunflower seeds, and mushrooms are all good food sources of iodide. The RDAB for iodide is proposed to be 170mcg daily.

Manganese functions both as an enzyme activator and as a constituent of metalloenzymes. A deficiency can cause impaired growth. It increases superoxide dismutase activity (SOD is a powerful anti-oxidant). This may help with the healing process. Some food sources include wheat bran, legumes, and nuts. The RDAB for manganese is set at 20 mg daily to avoid any deficiencies.

Molybdenum is a cofactor for four metalloenzymes: xanthine dehydrogenase, aldehyde oxidase, xanthine oxidase, and sulfide oxidase. These metalloenzymes function in many different reactions in the human body. Soybeans and pasta are some food sources of molybdenum. To prevent deficiency the RDAB for molybdenum is set at 200mcg.

Fluorine or fluoride (which is fluorine bound to either a metal, non-metal, or organic compound. It's major effects are related to it's effects on the mineralization of bones and teeth. It may decrease bone resorption so it is being used to treat osteoporosis. Some food sources include mackerel and sardines. The RDAB is established at 4 mg daily.

Silicon plays a vital role in the formation of bones, connective tissue, and cartilage. It hastens mineralization of bones as well as promotes growth. It has a positive influence on collagen synthesis and is also needed to form glycosaminoglycans (components of the fluid around joints). Food sources include many plant foods. Since bodybuilders may place stress on their joints through intense training, silicon is an important mineral. The RDAB is established at 20 mg per day.

Vanadium is present in all healthy tissue of all living things. It is both water and fat soluble. Vanadate is 3 to 5 times more efficiently absorbed than vanadyl (34). Vanadium is an insulin mimicker. In other words, it stimulates glucose uptake into cells and enhances glucose metabolism for glycogen synthesis. It has been shown that vanadate can control high blood glucose (35). Vanadyl may also increase creatine uptake in muscle cells (36). This is a pretty good mineral for bodybuilders because it may increase glycogen stores in muscle cells causing increased energy and sparing muscle proteins. It can also cause excellent "pumps" during training sessions. Foods contain very little vanadium. The RDAB is set at 10 mg daily of vanadium or preferably vanadate.

Boron influences the composition, structure, and strength of bones. It also plays a role on how certain minerals such as calcium are metabolized. Fruits and vegetables contain boron. The RDAB is set at 3 mg of boron daily.

The RDAB will give bodybuilders a better idea of the vitamin and mineral intake that is optimal for them. These are suggested intakes and recommendations. There are many instances where certain vitamins and minerals may be supplemented in excess of the RDAB. The RDAB is established to help prevent deficiency of certain vitamins and minerals and to optimize performance for bodybuilders. Body weight, gender, and exercise intensity may also play a role in determining vitamin and mineral intake. There are many quality vitamin and mineral formulas on the market. One way to make sure a vitamin mineral supplement will be absorbed for proper use in the body is to take the tablet and place it in a plastic bag with vinegar. If the vitamin tablet is dissolved within ½ hour , then the product probably will be beneficial. The pH of the stomach is about 3 which is the same pH as vinegar. The first part of the small intestine is where a lot of key nutrients are absorbed so if a vitamin tablet is dissolved by the time it reaches the first part of the small intestine, it will be most readily absorbed and used by the body. The RDA is a decent standard to prevent deficiency in normal individuals but the RDAB is a good standard for extraordinary people such as bodybuilders. Deficiencies of vitamins and minerals can be devastating to bodybuilders. So take your vitamins and minerals, train hard, and eat smart!

About the Author

Rehan Jalali is a nationally recognized sports nutritionist who has developed more than 100 cutting-edge products for the dietary-supplement industry. He has worked with and helped formulate products used by dozens of Olympic and professional athletes. He is also a natural bodybuilder, founder of the Supplement Research Foundation, and author of "The Secrets of Nutrition and Sports Supplements" and "The Six-Pack Diet Plan."

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