WEEK 10: MICRONUTRITION

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Functions of Copper

Copper is also an anti-oxidant and is involved in ATP production, collagen and elastin cross- linking, blood clotting, immune function and gene expression. (p.47, Micronutrition)

True or False? Vitamin D is water-soluble.

False. Since vitamin D is fat soluble, you should consume it with a meal with fats. (p.18, Micronutrition)

Recommended intake of Iodine

Go to your kitchen and check if your salt is iodized. If not, get some. And check that it actually contains enough iodine. You need at least 150 micrograms (0.15 mg) a day (the RDA) and you definitely shouldn't need more than 10 grams of table salt (NaCl) to reach that. The RDA increases during pregnancy to 220 mcg and during lactation to 290 mcg. (p.52, Micronutrition)

Should you consume a multivitamin that has much more than 100% of the recommend daily intake of nutrient?

No. As a rule of thumb, don't consume a multivitamin that has much more than 100% of the recommend daily intake of nutrients, unless you have a good reason. More specifically, you need to tailor your vitamin and mineral supplementation to your diet. (p.4, Micronutrition)

Recommendations for vitamin A intake

Recommendations for vitamin A intake are expressed as retinol activity equivalents (RAE) to account for differences in the biological activities of the carotenoids. (p.13, Micronutrition)

Vitamin D3 deficiency

See attached image

Recommended intake of Potassium

The Adequate Intake of potassium is 4.7 grams per day for adults. Your kidneys are extremely proficient at regulating potassium excretion, however, which gives you great flexibility for your daily intake and circumvents any toxicity risk for healthy individuals. (p.29, Micronutrition)

Recommended intake of Copper

The RDA for copper is set at 0.9 mg/day. This increases during pregnancy to 1 mg and during lactation to 1.3 mg. The Tolerable Upper Intake Level for copper is set at 10 mg/day, although intakes below this level may cause gastrointestinal discomfort in some individuals. (p.47, Micronutrition)

True or False? You should not combine vitamin C with a large dose of vitamin E.

True. A gram of vitamin C, at least when combined with a hefty dose of vitamin E, has been found to interfere with anabolic muscle signaling, strength development and long term muscle growth. (p.6, Micronutrition)

Food sources of Vitamin K

Vegetables, particularly green leafy vegetables, are the richest source of dietary vitamin K in the form of vitamin K1 (phylloquinone). Vitamin K2 (menaquinone) is present in large amounts specifically in fermented foods like aged cheese, as it is created by bacteria. To get 100 mcg of vitamin K, you'd need to consume green leafy vegetables, fermented foods or any of the following on a daily basis: - 2.5 cups of pumpkin -~4 cups of pomegranate juice - 170 g of pine nuts or almost 300 g of cashews - 3 cups of blueberries - 4.5 cups of grapes - 2 avocados (roughly a pound) (p.22, Micronutrition)

Functions of Zinc

Zinc is an essential mineral required for immune functioning, protein synthesis, testicular functioning, testosterone production and wound healing. Zinc deficiency directly causes lean body mass losses, which are restored by zinc consumption. Even marginal zinc deficiency stunts growth and human development. => Athletes need more zinc than sedentary individuals. (p.44, Micronutrition)

Why should we not worry too much about overdosing on salt and its relationship with blood pressure?

A meta-analysis found that salt reduction by ~4.4 g/d leads to a significant reduction in blood pressure. The mean changes in blood pressure were −4.18 mm Hg for systolic blood pressure and −2.06 mm Hg for diastolic blood pressure. Those are small changes relative to the healthy reference range. Blood pressure is considered normal when systolic blood pressure does not exceed 120 mm Hg and diastolic blood pressure does not exceed 80 mm Hg. The blood pressure categories (prehypertension, hypertension state 1, hypertension stage 2 and hypertensive crisis) are divided by 20 mg Hg intervals for systolic blood pressure and by 10 mm Hg intervals for diastolic blood pressure. So the blood pressure reduction that can be achieved by salt restriction is only about one fifth of the interval defining each blood pressure category. (p.25) The increase in blood pressure from a high sodium diet does not consistently translate into an increase in cardiovascular health incidents. And if you have hypertension (excessive blood pressure), a low salt diet alone is very unlikely to get you to the healthy range. A subsequent systematic review of the randomized controlled trials concluded that salt restriction does not have any clinically meaningful benefits. This conclusion was unchanged from a previous systematic Cochrane review on salt restriction's health effects and the famous NHANES I large-scale observational study. A recent review paper even directed itself at various government organizations: "Dietary salt restriction in heart failure: where is the evidence?" They found no good evidence for sodium restriction even in heart failure patients, let alone the healthy population at large. (p.25, Micronutrition)

Dietary supplement of Magnesium

All in all, to consume enough magnesium, your diet needs to be very good, especially during contest prep, or you need to supplement. If you choose to supplement magnesium, the form is very important. Most magnesium products contain magnesium oxide, which is cheap crap. You absorb virtually none of the magnesium oxide and it can irritate your digestive tract. The popular alternative magnesium glycinate (chelate) is hardly better absorbed than oxide, so it's also not recommended. Instead, you should supplement magnesium in the form of magnesium citrate or else magnesium chloride, magnesium lactate, magnesium gluconate or magnesium aspartate. The latter best salts are generally only 20-40% bioavailable, which is comparable to the poor food sources of magnesium mentioned above. So even the best supplementation can upset your gut and pose digestive problems. Magnesium supplements should NOT be taken with meals high in calcium or zinc, because calcium, magnesium and zinc compete with each other's absorption. (p.36, 37, Micronutrition)

Vitamin B's functions

B-vitamins are a class of related vitamins that function as co-factors or precursors (building blocks) for various metabolic processes, including energy production. (p.8, Micronutrition)

Food sources of Iron

Basically, without large amounts of animal flesh in your diet, preferably organ meat, you're at a serious risk of becoming iron deficient as an athlete. Almost all whole foods contain small amounts of iron. However, plants are poor sources of iron, because they contain non-heme iron. This is difficult to absorb for the body. To make things worse, many plants contain polyphenols and other phytochemicals that inhibit the absorption of iron. Legumes and grains are worst, because they also contain a lot of phytic acid that binds with the iron to make it unavailable for the human body. Phytic acid can reduce the bioavailability of iron by 2 to 5-fold. Even iron deficient people only absorb 2-3% of the iron in modern grains. Remember that next time a nutritionist shows you a food label of whole wheat bread to show you how nutritious it is. (p.39, 40, Micronutrition)

Functions of Calcium

Calcium is the most common mineral in the body, 99% of which is in your bones. Calcium is required for neuromuscular functioning, satiety signaling, the regulation of blood flow, bone health and a host of other processes. Athletes that consume more calcium gain less fat than athletes that consume little calcium, independent of energy intake. (p.32, Micronutrition)

Himalayan salt

Certain varieties of salt, like Himalayan sea salt, also contain trace amounts of other minerals, and have some color, often a pinkish glow. This is the result of less processing, as salt is produced by evaporating (sea) water. (p.24, Micronutrition)

Recommended intake of Chloride

Chloride an essential mineral that functions as an electrolyte. Chloride is found in similar amounts in similar locations as sodium, is absorbed similarly and has the same Adequate Intake and Upper Tolerable Intake as sodium in mmol. (In grams the AI is 2.3 g and the UTI is 3.6 g.) As long as your sodium intake is under control, your chloride intake will be as well. (p.31, Micronutrition)

True or False? You don't have to worry about Vitamin B12 as it's abundant in the body.

False. Vitamin B12 is exceptional as a water-soluble vitamin in that the body has around 2,500 mcg of it bound as co-factors to enzymes, mostly in the liver. This is not 'storage' in the traditional sense in that the vitamin B12 is actively in use and not in a reserve compartment for later use. Since the daily requirement is low relative to total body 'stores', deficiency typically takes years to develop, but once developed, it's hard to treat without injections. (p.11, Micronutrition)

True or False? Sea salt is highly recommended because of their high amount of iodine.

False. Note that sea salt does not contain sufficient amounts of iodine. This is a myth. In fact, sea salt generally only contains trace amounts of any kind of mineral. While you may find it more tasty than regular table salt, it is not considerably more nutritious in any way. As such, to obtain enough iodine from salt, the salt needs to be iodized. (p.52, Micronutrition)

True or False? You should not overdose on B-vitamins as there can be risks for toxicity.

False. There is virtually no toxicity risk for even extremely high intakes of B-vitamins - they are water soluble and thus easily excreted in the urine - and considering that B-vitamin complexes are cheap, vegetarians are recommended to take a daily B-vitamin complex with at least 100% of the RDI of all B-vitamins and 250 mcg of vitamin B12. (p.11, Micronutrition)

Food sources of vitamin C

Food sources of vitamin C primarily include fruits and vegetables. Excellent sources are asparagus, papaya, oranges, orange juice, cantaloupe, cauliflower, broccoli, brussels sprouts, green peppers, grapefruit, grapefruit juice, kale, lemons and strawberries. In practice, as long as your diet has several servings of plants on a daily basis, you should be covered for vitamin C. (p.7, Micronutrition)

Deficiency of Zinc

Global zinc deficiency is estimated to affect 17.3% to 31% of the population and female bodybuilders often don't consume enough zinc either. Zinc deficiency is probably even more common than we know. The majority of zinc is stored inside cells, so blood work is not very reliable to diagnose zinc deficiency. If your blood work shows you are zinc deficient, you probably are, but even if your blood work comes back ok, you may still be zinc deficient. Common symptoms that you can diagnose yourself include: - Poor skin quality, including acne and dry, scaling skin (xeroderma). - Inflammatory or microbial conditions of the mouth, such as white tongue coating or ulcers. - Poor hair quality, including thinning. More clear and severe symptoms include: - Compromised immune function, including impaired wound healing, frequent illness (including the flu) and inflammatory conditions. - Diarrhea. - Loss of appetite and decreased taste and smell. - Low testosterone and depression. (p.46, Micronutrition)

Food sources of Magnesium

Green leafy vegetables and seafood rank highly. Magnesium is most prevalent in chocolate/cacao, nuts, beans and grains. This is problematic, because legumes, cacao and grains are rich in phytic acid, which inhibits the absorption of magnesium by ~60%. Moreover, the modern processing and refining of wheat, rice and corn depletes 82-97% of magnesium. Since the agricultural revolution, magnesium has been depleted in the soil and water as well. So if commercially sold starches or legumes are your primary sources of magnesium, you need to consume a lot of them. It's not easy to consume enough magnesium. You need a high dietary fiber intake from minimally processed or traditionally prepared carbohydrate sources or a whole lot of green veggies or seafood. Low carbohydrate diets and most average diets rich in commercially prepared grains are at significant risk of suboptimal intakes. (p.35, Micronutrition)

Food sources of Iodine

If you can't purchase iodized salt or don't consume much salt, here are several good options to consume enough iodine in your diet. 1) Eat marine seafood (as opposed to freshwater fish) regularly. 2) Consume seaweed once or twice a week. Tip: roll vegetables or glutinous rice in nori (the black sheets of seaweed used in sushi rolls). 3) Consume dairy regularly. 6 Large eggs or 2 cups of milk or yogurt provide enough iodine for a day. (p.52, Micronutrition)

Dietary supplement of Calcium

If you choose to supplement calcium, you have to take into account that calcium, magnesium and zinc compete with each other's absorption. So you should take the calcium supplements with meals that are low in these minerals, particularly magnesium given its relatively large intake. (p.33, Micronutrition)

Food sources of Zinc

If your diet contains red meat or shellfish on a daily basis, you probably consume enough zinc. 300 g of beef or 500 g of pork or lamb provides ~15 mg of zinc in highly bioavailable form. Crab, organ meats, and lobster are great too. Oysters contain so much zinc that you barely need 100 g to get over 15 mg of zinc. Without red meat, organ meat or shellfish in your diet, it becomes difficult to consume enough zinc as an athlete. Most starches aren't the best sources of zinc, because the phytic acid in legumes and grains decreases the bioavailability of zinc by ~20%. You'd need to consume about a kilo of chicken, over 300 g of nuts or over a pound of beans a day. (p.45, Micronutrition)

Recommended intake of Sodium

In conclusion, there is an optimum level of sodium intake, not a maximum. Less sodium certainly isn't always better for your health. The sodium sweet spot (no pun intended) for cardiovascular health appears to be around 3-5 grams per day. Sodium restriction for strength trainees is more likely to be harmful than helpful. Our sodium requirements for optimal health are likely over 5 grams a day, over 3 times as much as many governments recommend. If you consume salt to taste without any restriction and avoid very high sodium junk foods, your sodium intake should naturally end up in the ideal range and there is no need to obsess over your exact sodium intake. (p.27, Micronutrition)

Vitamin A's supplementation

In general, a high protein, fibrous, whole foods-based diet should easily result in adequate vitamin A activity and there is no need for supplementation. (p.14, Micronutrition)

Functions of Iodine

Iodine is an essential trace element that your body uses to create thyroid hormones. It is primarily found in seawater and soil nearby the sea. This has become a problem, because modern drink water and salt are so refined that they are now devoid of iodine. 35% of the global population does not consume enough iodine, with estimates over 50% in Europe. (p.52, Micronutrition)

Deficiency of Iron

Iron deficiency is one of the most common micronutrient deficiencies in the world. It mostly affects developing countries, but athletes are at a high risk because exercise increases iron requirements. 43% of elite male athletes do not consume enough iron. Female trainees are at an even higher risk due to the monthly blood loss during menstruation and differences in iron metabolism. 52% of female athletes have been found to have iron deficiency, despite already consuming more iron than similar women that don't exercise. Female strength trainees should therefore strongly consider making organ meat, particularly liver and kidney, or seafood a staple in their diet. (p.39, 40, Micronutrition)

Functions of Iron

Iron is an essential mineral used in the creation of hemoglobin, found in red blood cells, and myoglobin, found in muscle cells. As you know, blood and muscle are kind of important for trainees. Iron deficiency particularly impairs oxygen transport and thereby your endurance capacity and your resistance to fatigue; it can also impair strength. Iron is also a co-factor for many enzymes and plays a role in ATP production, amino acid metabolism, niacin synthesis, anti-oxidant functioning, hormone synthesis, carbohydrate metabolism and DNA synthesis. (p.39, Micronutrition)

Deficiency of Calcium

It is so important that your body maintains the calcium concentrations in most tissues so tightly that it will rather cannibalize its own bone tissue to get enough calcium than allow calcium deficiency in any other body part. (p.32, Micronutrition)

Why most of the researchs on sodium is associated with negative health results?

It's true that a high sodium intake has been associated with increased blood pressure, cardiovascular disease (CVD) and stroke. However, much of the research on health effects comes from epidemiology: it's cross-sectional, observational research, with less support from the scientific gold standard: randomized controlled trials. Since it's primarily highly processed junk foods that have very high amounts of sodium, correlations in observational research beg the question if it's actually the sodium intake in the diet and not just the overall diet that puts these individuals at an increased risk of heart-related incidents. (p.24, 25, Micronutrition)

Dietary supplement of Iron

Lacto-ovo vegetarians will often have to resort to iron supplementation or large amounts of eggs. Vegan athletes almost invariably benefit from supplementation. If you choose to supplement iron, be careful. There is high genetic interindividual variability in iron uptake from the diet and iron toxicity is a serious concern, especially for men: - Excessive iron consumption increases your risk of cancer. - Many iron supplements irritate the digestive tract. - Too much iron consumption can even shorten your life expectancy. Plus, once you have saturated your body's iron reserves, everything spills into the blood and the only way to get rid of it then is to get rid of some of your blood (i.e. donation). (p.41, Micronutrition) If you do decide to supplement iron, ferrous iron salts are better absorbed than ferric iron salts. Other forms of iron, such as heme iron polypeptides, carbonyl iron, iron amino-acid chelates, polysaccharide-iron complexes often result in fewer digestive side effects, so they may be preferable. (p.43, Micronutrition)

Deficiency of Magnesium

Magnesium deficiency can impair sleep quality via several mechanisms. 1) Magnesium is involved in activating the parasympathetic nervous system to put you in 'rest and digest' mode instead of 'fight of flight' mode. 2) Magnesium regulates the secretion of the sleep hormone melatonin. 3) Magnesium can bind to gamma-aminobutyric acid (GABA) receptors. GABA is a neurotransmitter that makes you calm. (p.34, Micronutrition)

Functions of Magnesium

Magnesium is one of your body's most abundant and important minerals and electrolytes. A healthy body contains 22-24 g of magnesium. The results of insufficient body magnesium include insulin resistance, low testosterone, depression, bone loss, stress hypersensitivity, high blood pressure and disturbed neuromuscular functioning. Getting enough magnesium can thus increase your testosterone, strength and endurance level, as well as decrease your stress levels. Magnesium also regulates sleep. Research in healthy, young individuals is scarce, but magnesium supplementation has been found to counteract the loss of exercise tolerance during sleep deprivation, to reduce insomnia and improve sleep quality in the elderly and to improve sleep quality in alcoholics that weren't magnesium-deficient. (p.34, Micronutrition)

Why should you not supplement multivamins?

Most multivitamins are absolute crap. A few of the common problems include: 1) Most multivitamins employ cheap manufacturing methods that result in nutrients that are not bioavailable: the body cannot absorb them well. For example, most of the magnesium in multivitamins is magnesium oxide. 2) Most multivitamins only contain cheap isoforms, which results in poor bioavailability and worse, an imbalanced ratio of isoforms in the body. 3) Most multivitamins massively overdose cheap nutrients that are easy to consume in your diet. Manufacturers do this because people and bodybuilders in particular are easily deceived by thinking more is better (while at the same time still being deficient in other micronutrients). Not only is this useless, over-supplementation can be harmful because many vitamins and minerals interact and overconsumption of one can cause deficiency of the other even in the presence of adequate intake. Many nutrients also act differently depending on the dosage. 4) Most multivitamins lack micronutrients that many people are actually deficient in, such as vitamins D and K and the minerals calcium, magnesium, iron and iodine, because mega-dosing minerals can be toxic. 5) Multivitamins often contain massive amounts of anti-oxidants that can interfere with the inflammatory signal for cell repair. (p.3,4, Micronutrition)

Functions of Phosphorus

Phosphorus is a shockingly unexciting mineral, yet it is important for many things in the body, including bone mineralization, DNA formation, ATP metabolism, cell membrane structure and acid-base balance. (p.38, Micronutrition)

Functions of Potassium

Potassium is an essential mineral. The average body stores 200-300 g of potassium, almost all within cells, which functions as an electrolyte essential for our survival. Together with sodium, which is found mainly in extracellular space, notably plasma, potassium regulates your body's fluid volumes by forming electrochemical gradients. These gradients are also needed for nerve transmission, muscular contractions, blood pressure regulation and kidney functioning. You also need potassium for good calcium absorption, insulin secretion and to maintain acid-base balance. (p.29, Micronutrition)

Food sources of Potassium

Potassium is found in almost all whole foods, notably animal and fish flesh, fruit and vegetables, as well as dairy, tea and coffee. As such, any whole food-based diet generally maintains sufficient potassium levels and neither deficiency or toxicity are a concern. (p.29, Micronutrition)

Deficiency of Vitamin K

Problematically, vitamin K deficiency is difficult to diagnose. Bloodwork can only show vitamin K levels in serum, not the vitamin K in the intestines. So doctors commonly test vitamin K deficiency by seeing how long it takes for your blood to clot. Yet lack of clinical blood clotting problems does not necessarily guarantee maximal health benefits. (p.22, Micronutrition)

Recommended intake of Vitamin E

Recommendations for vitamin E are based upon intake of the natural form (RRR) of α- tocopherol. The RDA for vitamin E for adults is 15 mg (22.4 IU) of RRR α-tocopherol. During lactation, recommendations are slightly higher at 19 mg (28.4 IU). (p.19, Micronutrition)

Functions of Salt

Salt not only increases the flavor of food to a completely different level, it's also very useful as a preservative due to its anti-microbial function. (p.24, Micronutrition)

Vitamin D3 supplements

Since virtually the entire population in Northern countries sees little strong sunlight and there is very little vitamin D in food (anyone saying any food is a good source of vitamin D is clueless), this means almost everyone benefits from supplementation. Even most outdoor athlete populations have a deficiency prevalence of over 44%, not to mention the percentage with a suboptimal level. Almost all untanned individuals are advised to supplement at least 2k IUs vitamin D3 per day, going up to 9k depending on sun exposure, bodyweight, skin type and diet quality. (p.17, Micronutrition)

Dietary supplement of Iodine

Supplement it. Kelp capsules are the most popular form. The iodine content of seaweed is extremely variable though. Just one gram can contain anywhere from 16 to 2,984 micrograms. Overconsumption is rare, as your thyroid autoregulates its production very well. The Japanese routinely eat over 1200 mcg, up to 80.000 in the Northern coastal regions. Dosages of 4.6 grams a day have been tolerated safely for years in research. (p.53, Micronutrition)

Complete blood count (CBC).

The CBC measures many parts of your blood. This test checks your hemoglobin and hematocrit (hee-MAT-oh-crit) levels. Hemoglobin is an iron-rich protein in red blood cells that carries oxygen to the body. Hematocrit is a measure of how much space red blood cells take up in your blood. A low level of hemoglobin or hematocrit is a sign of anemia. The CBC also checks the number of red blood cells, white blood cells, and platelets in your blood. Abnormal results may be a sign of infection, a blood disorder, or another condition. Finally, the CBC looks at mean corpuscular volume (MCV). MCV is a measure of the average size of your red blood cells. The results may be a clue as to the cause of your anemia. In iron-deficiency anemia, for example, red blood cells usually are smaller than normal. (p.42, 43, Micronutrition)

Vitamin B's recommended intake and supplement

The RDA for adults for vitamin B12 is 2.4 μg/day, but 4 μg/day may be better for optimal health. Consuming enough vitamin B12 is further complicated by the need to consume it frequently, because its oral bioavailability decreases dramatically above intakes of 2 mcg. Your body absorbs only ~13 mcg of a 1,000 mcg intake. In contrast to most nutrients, bioavailability is even lower when taken with a meal and it's better to consume vitamin B12 supplements fasted. Due to the low and highly variable bioavailability of oral vitamin B12, many doctors prefer intramuscular injections to correct deficiency. A high protein diet inherently takes care of B-vitamin requirements. Vegetarians will likely need to supplement a B-vitamin complex, notably including 4+ mcg vitamin B12. (p.10, 11, 12, Micronutrition)

Recommended intake of Phosphorus

The RDI is 700 mg/day. Phosphorus is abundant in protein-rich animal foods, so a high protein diet tends to automatically take care of phosphorus requirements. Even vegetarians are not at much of a risk of deficiency, as many grains contain lots of phosphorus and a high vegetable intake can cover your requirements as well. You can even get a lot of phosphorus from soft drinks. (p.38, Micronutrition)

Toxicity Risk of Iron

The Tolerable Upper Intake Level for iron for adults is 45 mg. (p.41) Due to the risk of iron toxicity, unless you have good reason to believe iron insufficiency, have bloodwork done first to check the indicators of your iron level: 1) Serum iron: This test measures the amount of iron in your blood. The level of iron in your blood may be normal even if the total amount of iron in your body is low, so you should also do the following tests. 2) Serum ferritin: Ferritin is a protein that helps store iron in your body, so its level tells you how much of your body's stored iron has been used. Low ferritin levels are a clear sign of iron deficiency. High levels do not necessarily mean iron overload, however, as ferritin functions like an acute phase reactant, so inflammation can also elevate it. 3) Transferrin level, or total iron-binding capacity: Transferrin is a protein that carries iron in your blood. Total iron-binding capacity measures how much of the transferrin in your blood isn't carrying iron. If you have iron-deficiency anemia, you'll have a high level of transferrin that has no iron. (p.42, Micronutrition)

Tolerable Upper Intake Level of Calcium

The Tolerable Upper Intake Level is 2,500 mg, beyond which gastrointestinal side- effects can occur, but given that your body can only absorb ~800 mg of calcium per serving, it makes no sense to consume this much in the first place. (p.33, Micronutrition)

Food sources of Calcium

The best food sources of calcium include dairy products, especially milk, cheese and yogurt, and selected seafood, such as salmon, sardines (with bones), clams and oysters. Selected vegetables, such as turnips, mustard greens, broccoli, cauliflower and kale also provide relatively large amounts of calcium. Legumes and legume products, especially tofu (soybean curd) and nuts, provide some calcium. Some vegetables such as spinach, rhubarb and Swiss chard also are poor sources because they contain large amounts of oxalic acid, which binds calcium and inhibits its absorption. (p.32, Micronutrition) In practice, to get the maximally beneficial amount of calcium from food, you need to eat dairy, sardines, lots of salmon or a ton of vegetables. Given this, it's no surprise that dairy-fearing bodybuilders are at serious risk of calcium deficiency. (p.33, Micronutrition)

Recommended intake of Zinc

The current recommended daily intake for zinc is 11 mg for adult men and 8 mg for women (13 mg when pregnant or lactating). However, the current zinc recommendations are based on outdated measurement methodologies that underestimate zinc requirements by nearly 50%. If we then add a ~20% increase in zinc requirements for intensive exercise, the recommended daily intake become 20 mg for men and 14 mg for women. Upward of 20 mg of zinc supplementation can decrease HDL cholesterol levels and induce copper deficiency. The Tolerable Upper Intake Level for zinc has been set at 40 mg daily based on its interaction with copper. (p.44, Micronutrition) Zinc supplementation can also significantly increase your appetite, even if you're not deficient in zinc, which is generally undesirable. Zinc only has a few limited storage sites in the body, so you need to consume it regularly, ideally daily. (p.44, Micronutrition)

Recommended intake of vitamin K

The daily Adequate Intake for vitamin K has been set at 120 mcg for men and 90 mcg for women or 1 mcg per kilogram bodyweight. (p.20, Micronutrition)

Functions of Flouride

The major functions of fluoride are related to its effects on bone mineralization and the formation of dental enamels. Fluoride increases the resistance of enamel to acid demineralization and increases tooth mineralization. Read: it's good for your teeth, which is why it's often in your toothpaste and the water supply. It's also in your food, unbeknownst to many people. That's pretty much all you need to know. (p.58, Micronutrition)

Recommended intake of Magnesium

The recommended daily intake (RDI) of magnesium is 6 mg/kg/d, roughly ~400 mg for the average man and ~300 mg for a woman. Athletes likely need at least 20% more due to the increased need for magnesium during muscle repair and increased magnesium losses via sweat and urine. It's not easy to consume that much magnesium. Many athletes have low magnesium levels, even though they typically eat a lot of magnesium rich starches as part of their high carb diets. Only 15-50% of Americans are estimated to consume enough magnesium. (p.34, Micronutrition)

Recommended intake of Calcium

The recommended dietary allowance for calcium is one gram, but during periods of growth this rises to 1.3 grams, so for strength trainees that's an advisable minimum. (p.32, Micronutrition)

Recommended intake of Iron

The recommended dietary intake is 18 mg for women (more when menstruating, pregnant or lactating) and 11 mg for men. Athletes need up to 50% more, depending on how much they exercise. (p.39, Micronutrition)

Food sources of Copper

The richest sources of copper are meats (especially organ meats like liver) and shellfish (especially oysters and lobster). Plant food sources rich in copper include nuts (especially cashews), seeds, legumes and dried fruits. Potatoes, whole grains and cocoa are also good sources. In contrast, milk and dairy products are poor sources of the mineral. As you can see, it's not difficult to consume enough copper in a whole foods-based diet. Vegetarians need to pay attention to it though. (p.47, Micronutrition)

Vitamin D's toxicity

There is very little risk associated with mega-dosing vitamin D. However, supplementation can lead to excess vitamin D levels because it circumvents the negative feedback loop of natural vitamin D production. Vitamin D intoxication only reliably occurs when serum levels exceed 200 ng/mL 25(OH)D though, which generally requires 20k+ IUs of vitamin D3 supplementation. (p.18, Micronutrition)

True or False? Vitamin E is lipid-soluble.

True. As a fat-soluble vitamin, vitamin E's absorption is much higher in a fatty meal. (p.19, Micronutrition)

True or False? You should supplement Sodium if you're training in the heat for long hours.

True. Exercise greatly increases sodium requirements: aerobic exercise in the heat can cause sodium losses in sweat of up to 5.5 grams of sodium per hour(!) A regular indoor strength training workout tends to cause 1-2 grams of sodium loss. (p.28, Micronutrition)

True or False? Vitamin K is a fat-soluble vitamin.

True. While vitamin K is a fat-soluble vitamin, for effective absorption you need to consume it with a fatty meal. The body does not retain it very effectively, so you need to consume it on a weekly, preferably daily, basis to prevent deficiency. (p.22, Micronutrition)

True or False? Vitamin A and carotenoids are lipid-soluble and should be consumed in fatty meals.

True. Vitamin A and carotenoids are lipid-soluble, so their absorption is higher in fatty meals. (p.15, Micronutrition)

True or False? Excessive use of Vitamin A may interfere with vitamin K absorption.

True. Vitamin A and carotenoids interact with vitamins E and K. Excess vitamin A intake interferes with vitamin K absorption. High β-carotene intake may decrease plasma vitamin E concentrations. (p.13, Micronutrition)

Why should you not consume vitamin E from supplements?

Unbeknownst to many people, vitamin E is not just a single compound. Many multivitamins only include alpha-tocopherol, because many people think this is vitamin E. In fact, vitamin E has 8 isoforms/vitamers with different functions and over- supplementation of one of them causes competitive uptake inhibition of the others, potentially causing a deficiency and imbalance of the isoforms in the body. Synthetic vitamin E is only 74% as bioavailable as the vitamin E found in food. In other words, the body absorbs 26% less vitamin E when it comes from a supplement instead of whole foods. Since supplementation can disrupt the balance of vitamin E isoforms and high doses of vitamin E can impair training adaptations, including muscle growth, by excessively suppressing inflammation, whole foods are the preferred source of vitamin E in the diet. (p.19, Micronutrition)

Forms of Vitamin K

Unbeknownst to many, there 2 natural forms of vitamin K: K1 (phylloquinone) and K2 (menaquinone). 1) Vitamin K1 is found in plants and is commonly the primary source of vitamin K in the diet. 2) Vitamin K2 is produced by bacteria in foods such as cheese and natto. (p.20, Micronutrition)

Why vegetarians need to pay attention to their Vitamin B's level?

Vegetarians are a notable exception. Vitamin B12 is practically only found in animal foods, which have derived their cobalamins from micro-organisms. Any vitamin B12 found in plant foods can likely be traced either to contamination with microorganisms from manure (yes, shit) or, in the case of legumes, to the presence of nitrogen-fixing bacteria in the plant root nodules. (p.10, Micronutrition)

Vitamin A's functions

Vitamin A is essential for vision as well as for cellular differentiation, growth, reproduction, bone development and immune system functions. Carotenoids also function as anti-oxidants. (p.13, Micronutrition)

Food sources of Vitamin A and Caratenoids

Vitamin A is primarily found in animal foods, especially liver. Carotenoids are more commonly available in plants. They are part of the pigments that give plants their yellow, orange and red colors, so these colored plants tend to be high in carotenoids. A high intake of carotenoids will also give your skin a yellow tint. (p.14, Micronutrition)

Vitamin A - Caratenoids

Vitamin A, also called preformed vitamin A or retinoid. (p.13, Micronutrition) Vitamin A is closely related to carotenoids, often referred to as provitamin A, which represent a group of compounds that are precursors of vitamin A. However, only a minority of carotenoids convert to retinol and exhibit vitamin A activity. A popular carotenoid is β-carotene. (p.13, Micronutrition)

Vitamin C's function

Vitamin C is a water-soluble anti-oxidant. It prevents free radical damage and oxidative stress, thereby keeping inflammation in check. This makes it very important for your immune system. Vitamin C is crucial to produce all the following compounds, which are needed for good connective tissue health, energy production and brain functioning: • Collagen • Carnitine • Tyrosine • Norepinephrine • Serotonin (p.5, Micronutrition)

Vitamin C's recommended intake

Vitamin C's Recommended Dietary Allowance (RDA) for adult men is 90 mg; 75 mg for women. These intakes are widely regarded as insufficient for optimal health, especially for strength trainees: it's better to consume 120-200 mg per day. Healthy individuals should generally avoid supplementary doses over 250 mg. (p.6, Micronutrition)

Recommended intake of Vitamin D

Vitamin D requirements have been colossally underestimated by public health authorities for a long time. Meta-analytic research finds all-cause mortality decreases up to at least 50 nmol/l, so that should be the minimum for good health. Evidence for benefits goes up to 100 nmol/l and higher for diabetics. For maximum benefit, aim for a serum 25-hydroxyvitamin D level of ~115 nmol/l. (p.16, 17, Micronutrition)

Vitamin D3

Vitamin D3 (cholecalciferol) is an essential vitamin produced naturally by the skin after exposure to ultraviolet radiation, particularly UVB, like in sunlight. (p.16, Micronutrition)

Vitamin D3's functions

Vitamin D3 is important for strength trainees, because it is necessary for optimal bone strength, mineral metabolism, immune function, neuromuscular functioning and testosterone synthesis. As a result, your vitamin D level influences strength development and injury resistance. (p.16, Micronutrition)

Vitamin E's functions

Vitamin E is an anti-oxidant. It plays important roles in cell membranes and cell signaling. (p.19, Micronutrition)

Food sources of Vitamin E

Vitamin E, in its various forms, is found primarily in plant foods, especially the oils from plants in nuts. Green vegetables are also rich in vitamin E. A whole foods-based diet with green vegetables should ensure adequate vitamin E status. (p.19, Micronutrition)

Vitamin K's functions.

Vitamin K is required to form coagulation factors. Without those, your blood won't clot effectively and you will easily bruise and bleed excessively. Vitamin K also interacts with vitamin D and calcium during bone formation. (p.20, Micronutrition)

Dietary supplement of Potassium

Vomiting, diarrhea and diuretic use notably increase potassium excretion and thereby the risk of potassium deficiency (hypokalemia). Symptoms include malaise, constipation, muscle weakness and fatigue. Potassium supplementation can prevent this, but above ~100 mg, digestive problems often result from supplementation, which largely defeats their purpose, especially since it's primarily digestive problems that give rise to potassium deficiency. Potassium supplementation is also risky because of its large amounts and rapid absorption, which can be lethal in certain cases. As such, potassium supplementation above 100 mg per day is generally inadvisable. (p.30, Micronutrition)

Why should you supplement vitamins as a strength trainee?

We can say though that there is no need for a multivitamin if your diet is already good. That's a big if though. Nutrient deficiencies are common, especially during weight loss diets, even in people that pay a lot of attention to their diet. Many strength trainees think if you eat a diet that mostly consists of whole foods, you're covered. You're not. Depending on which study you look at, over 50% of bodybuilders' diets are do not meet the recommended daily intakes of several micronutrients and that's not even taking into account their higher requirements compared to sedentary individuals (p.3, Micronutrition)

Sources of Vitamin D3

You can achieve recommended serum concentration with 10-30 minutes of daily near-full-body sun exposure with a UV index of ~3+. The exact time required depends on how dark someone's skin is. The darker someone's skin, the more sun exposure they need. The sun exposure needs to be direct, because glass and sunscreen block ultraviolet radiation. Tanning beds are also effective, but since they consist of ~95% UVA instead of B, you need relatively more radiation to achieve the same vitamin D biosynthesis. (p.17, Micronutrition)

Dietary supplement of Vitamin K

You can supplement vitamin K1 in the form of phylloquinone and vitamin K2 in the form of menaquinones (MK-4, MK-7, MK-8 or MK-9). (p.22, Micronutrition)


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