A controlled and planned vegetarian diet is nutritionally beneficial for health and for the prevention of certain diseases. It is particularly important for vegetarians to avoid consuming refined products, which are stripped of a large portion of their nutrients. It is also important to consume enough calories. This can be challenging for some vegetarians who deliberately choose to reduce their food intake or who overconsume fibers that can interfere with mineral absorption. Good weekly meal planning is necessary because some essential nutrients, mainly provided by animal products, can be obtained through combinations of plant-based foods. To maintain optimal health, it is particularly important for vegetarians to consume certain nutrients in adequate amounts, either from foods, enriched foods, or nutritional supplements.
Proteins
Most adults need about 0.8 grams of protein per kilogram of body weight. Vegans who do not eat dairy products, eggs, or fish need to eat 10 to 20% more protein than recommended to compensate for the lower digestibility of plant proteins. For vegetarians, it is easier to find sources of protein in their daily diet.
Sufficient Protein Intake
Include in your daily diet a wide variety of plant-based protein-rich foods such as legumes, soy-based products like tofu, tempeh, whole grains, nuts, seeds, dairy products, and eggs. Legumes are an important source of lysine, the essential amino acid most likely to be deficient in a vegetarian diet. Combine 2 to 3 servings of legumes (beans, peas, and lentils) daily with grains (rice and beans, bread and hummus, couscous and chickpeas, etc.).
Iron
The recommended daily intake (RDI) of iron for vegetarians is 1.8 times higher than for non-vegetarians: 27 mg vs. 15 mg, as iron from plant foods is not as available to the body as iron from animal sources. Although iron intake and reserves are generally sufficient in vegetarians and vegans, women and young athletes should be particularly vigilant to ensure their needs are met. In addition, lacto-ovo-vegetarians who consume large amounts of dairy products or eggs and fewer legumes should be aware that dairy products are not a good source of iron and inhibit iron absorption. The iron in eggs also has low bioavailability.
Sufficient Iron Intake
Consume a wide variety of iron-rich foods on a daily basis. Increase iron absorption by eating iron-rich foods with vitamin C-rich foods (be cautious, this has the opposite effect if you combine vitamin C and iron-rich dietary supplements). Decrease foods that inhibit iron absorption in the diet. These include phytates found in wheat bran and soy and tannins found in tea, coffee, and chocolate. The amounts of phytates in soy can be reduced by sprouting or fermenting, such as in miso or tempeh.
- Legumes, especially chickpeas, azuki beans, lentils, and red beans.
- Nuts and seeds, particularly cashews, almonds, pumpkin seeds, sunflower seeds, and tahini (sesame seed paste).
- Whole grains and enriched grains such as quinoa, dried fruits.
- Dark leafy green vegetables (parsley, watercress, dandelion, spinach, fennel, sorrel, nettle, etc.).
Zinc
The bioavailability of zinc from plant sources is lower than from animal sources, so marginal zinc deficiencies are common in vegetarians. This is due to compounds called phytates, which are potent inhibitors of zinc absorption, especially when consumed in combination with calcium and iron. In addition, plant foods tend to have lower zinc concentrations than animal foods. Vegetarians may need 50% more zinc if their diet is high in phytates.
Sufficient Zinc Intake
Eat a variety of zinc-rich foods every day: legumes (azuki beans, white beans, and split peas), nuts and seeds (pumpkin seeds, sunflower seeds, and cashews), whole grains and wheat germ. Minimize zinc absorption inhibitors by avoiding combining calcium (nutritional supplements or foods) and zinc-rich foods, or zinc-rich foods with phytates. Prefer wheat germ to wheat bran, which contains significant amounts of phytates. Increase zinc bioavailability by soaking (beans, for example), sprouting (cereal grains, legumes, or vegetables), and fermenting foods (sourdough bread, brewer's yeast, etc.).
Iodine
Iodine is an essential mineral necessary for thyroid function. Too much or too little iodine in the diet can lead to hypothyroidism, a precursor to diseases. Vegetarians and vegans generally consume less iodine than the general population, but this varies depending on their consumption of iodine-rich nutritional supplements, iodized salt, and seaweed. Vegans who do not consume iodized salt may risk iodine deficiency. Iodine absorption is inhibited by naturally occurring compounds in so-called goitrogenic foods. Goitrogenic foods include soy and soy products, sweet potatoes, millet, flaxseeds, and cruciferous vegetables such as broccoli, cauliflower, kale, and cabbage. Raw vegetables are more goitrogenic than cooked vegetables. However, consuming these foods poses no problem for healthy individuals who ingest sufficient amounts of iodine.
Sufficient Iodine Intake
The recommended daily intake (RDI) for iodine is 150 mcg, which translates to 1/2 teaspoon of iodized salt or 1/10 teaspoon of kelp powder.
The upper limit of iodine is 1100 mcg. Seaweeds contain high levels of iodine, so be careful not to consume excessive amounts.
Essential Fatty Acids
Essential fatty acids are aptly named because they are truly essential for health. Since the body cannot make them, they must be provided by the diet. Omega-3s are a class of essential fatty acids that include ALA (alpha-linolenic acid), EPA (eicosapentaenoic acid), and DHA (docosahexaenoic acid). EPA and DHA, in particular, are important for maintaining cell membranes, including those of the brain and eyes, as well as for regulating bodily processes. It is often observed that vegetarian and especially vegan diets do not provide sufficient amounts of omega-3 fatty acids. On the other hand, vegetarian diets may provide excessive amounts of omega-6 fatty acids, another class of essential fatty acids found in vegetable oils from corn, soy, grape seeds, in bread and whole grains. Consuming too much omega-6 compared to omega-3 promotes inflammation and creates imbalances harmful to health. The recommended omega-6/omega-3 ratio is 2 to 1. However, in vegetarians, it is more often 10 to 1. This is why omega-6 intake should be monitored.
Sufficient
Omega-3 Intake
Increase omega-3 consumption by taking DHA supplements (microalgae), consuming seaweed and eggs enriched with omega-3. It is recommended to achieve an intake of 200-300 mg per day of EPA/DHA. Supplementation is particularly important for pregnant and lactating women and people with diabetes or hypertension whose bodies cannot produce EPA or DHA from ALA.
Eat foods or take supplements rich in alpha-linolenic acid (ALA) from which the body can make EPA and DHA. ALA is found in flaxseed oil, hemp oil, walnuts, and rapeseed oil. If your main source of omega-3 fatty acids is ALA, your needs may be higher since the conversion of ALA to EPA and DHA in the body is inefficient. It is recommended to consume 4 grams of ALA per day.
Avoid trans fatty acids found in hydrogenated or partially hydrogenated fats as well as excessive amounts of alcohol, both of which inhibit the enzymes that help produce EPA and DHA. Prefer monounsaturated fatty acids, such as those found in olive oil and rapeseed oil.
Vitamin B12
It is difficult to maintain sufficient levels of vitamin B12 in a vegetarian diet. A deficiency in vitamin B12 intake can negate the preventive effect of the vegetarian diet on cardiovascular diseases. Vitamin B12 supplementation is strongly recommended. This is particularly true for vegans and pregnant women for whom optimal vitamin B12 intake is essential. The only reliable sources of vitamin B12 are animal foods, fortified foods, or supplements. Algae are not a reliable source because they generally contain vitamin analogs that are not physiologically active. Fermented foods, such as tempeh and miso, and organic vegetables are also low in vitamin B12.
Sufficient Vitamin B12 Intake
Eat foods enriched in vitamin B12: meat substitutes, cereals, beverages, and nutritional yeast. The recommended intake is at least 3 mcg in 2 or more meals. Absorption is better when small amounts of vitamin B12 are consumed at frequent intervals.
Supplement with vitamin B12 (10 mcg per day). All individuals over 50 should supplement with vitamin B12, as the body's ability to extract vitamin B12 from food decreases with age.
Lacto-ovo-vegetarians find vitamin B12 in eggs and dairy products.
Calcium
Calcium is essential for overall body health, necessary for the proper functioning of muscles, nerve function, and for the strengthening of bones and teeth. Vegans are more likely to have lower calcium levels than the general population. Deficient protein intake may also contribute to low bone density.
While dairy products have long been touted as the best source of calcium, it is known that some green vegetables such as broccoli, kale, collard greens, okra, and Chinese cabbage are a more bioavailable source of calcium. Plant foods also have the additional advantage of providing vitamins and minerals that contribute to bone health, such as vitamins C and K, folic acid (vitamin B9), magnesium, potassium, and boron. Note that calcium absorption may be negatively affected by high consumption of sodium, caffeine, protein, or sodas.
Sufficient Calcium Intake
Include highly absorbable calcium sources in the diet, such as the aforementioned leafy green vegetables. Other sources include dairy products, tofu, soy beverages, sesame seeds, almonds, legumes, dried figs, and other foods enriched in calcium. Note that spreading a variety of calcium-rich foods throughout the day promotes calcium absorption.
Some substances can interfere with calcium absorption. Eat foods containing phytates and oxalates (found in spinach, chard, beets, rhubarb, etc.) at different times from calcium-rich foods.
Vitamin D
Sufficient amounts of vitamin D can be produced by sun exposure during warm months: 10-15 minutes per day on the face and forearms for light-skinned people or 30 minutes to 3 hours for dark-skinned people. During colder, less sunny months, it is advisable to consume vitamin D-enriched foods or nutritional supplements.
Sufficient Vitamin D Intake
Expose yourself to the sun during the warm season as described above.
Consume foods rich in vitamin D: cow's milk, fortified soy beverages and cereals, egg yolks, mushrooms, seaweed, and certain yeasts.
Supplement with plant-based vitamin D2 (less bioavailable than D3).
Sources : wholefoodsmarket.com