Vegan and Vegetarian diets : Are these diets really healthy?
We all see that vegetarian and vegan diets are getting more and more popular. So many people defend these diets for several reasons and maybe they are even trying to convince you to be a vegetarian/vegan too.(It's happened to me ) But it's really hard to change a habit plus a habit which you enjoy. Personally, I really like to consume meat and dairy products and I can't imagine a life without them :D. (Of course, I like to eat fruit and vegetables too) Let's have a look at some articles which I found to help you form a sound opinion about this issue.
Health Effects of Vegetarian Diets
Plant-based diets have a role in decreasing the risk of chronic diseases like cardiovascular disease(CVD), cancer, and type 2 diabetes. The American Institute for Cancer Research promotes a plant-based diet which means you should get two-thirds of your food intake from vegetables, fruits, whole grains and beans. In the latest American Dietary Guidelines(2015-2020), vegetarian diets are suggested as one of the healthiest dietary patterns. But you should be careful! Because the adaptation of vegetarian diets can cause some nutrient deficiencies, however, these can be prevented with a proper diet plan. If a vegetarian diet is balanced, it will be rich in dietary fiber, complex carbohydrate, n-6 fatty acids, folate, magnesium, vitamin C and E. On the other hand, conversely to a Mediterranian or omnivorous diet, vegetarian diets, especially vegan ones, are prone to being lower in protein, n-3 fatty acids, zinc, calcium, vitamin A and B12. That's because these diets lack red meat, animal protein and/or dairy products.
Protein
Plant origin proteins have lower biological values than animal origin protein and it is in a less usable form. But vegetarian and vegan diets provide enough protein intake when the energy intake is adequate. When you eat a variety of plant foods( soy protein, textured vegetable protein, legumes, nuts, seeds and grains..) during the day, it gives you all essential amino acids which you need, if the calories in the diet are enough. Continuous intake of soy products and legumes will supply enough protein intake for vegetarians and also provide other indispensable nutrients.
N-3 Fatty Acids
Vegetarian and vegan diets might be low in n-3 fatty acids(alpha-linolenic acid), especially marine source fatty acids (eicosapentaenoic acid(EPA), docosahexaenoic acid(DHA)) and high in n-6 fatty acids(linoleic acid). Plant-based n-3 fatty acid can be converted to EPA and DHA, but it is not enough and conversion can be inhibited by high consumption of n-6 fatty acids. For the maintenance of immune, cognitive and cardiac function, these long-chain fatty acids are important. You can consume plant-based n-3 fatty acid sources (flax, chia, canola and hemp seed, walnuts and their oils) and supplements to provide adequate n-3 fatty acid levels.
Iron
In a recent study, it was found that iron absorption differs from %1 to %23 depending on three sets of factors: iron status, inhibitors, and enhancers. It might surprise you to learn that vegetarians consume as much or maybe a bit more iron than omnivores, although vegetarians have lower iron stores when compared with nonvegetarians. We should know that a person's iron status can be influenced by physiological needs and that iron stores can affect iron absorption. Plant-based foods include non-heme iron and this is more easily affected by inhibitors (phytates, soy protein, polyphenols and tannins). If you are a vegetarian, don't drink tea or coffee just before or just after a meal! Also absorption of non-heme iron can be enhanced up to10 times if the person is iron deficient. You can increase your iron absorption by moderating your diet if you have low iron status. Iron absorption can be increased by consuming enhancers such as ascorbic acid with your meal. Include parsley or kiwi fruit or an orange with your meal, for example. In general, vegetarians should aim for roughly double the iron intake of non-vegetarians.
Zinc
The great majority of zinc sources are found in animal products. Plant replacement zinc sources are legumes, whole grains, nuts and seeds (admissible source). Besides, zinc bioavailability is decreased by high levels of calcium supplementation and phytate (found in legumes, whole grains, nuts and seeds).Studies show us that vegetarians' zinc intakes are a little lower than nonvegetarians and they have lower serum zinc concentrations but still usually in the range. Sproutıng beans or legumes increases zinc levels and zinc absorption as does adding ascorbic acid.
Iodine
Vegans can have iodine deficiencies because plant-based diets can lack iodine. If key vegan iodine sources (iodized salt or sea vegetables) are not consumed by vegans, they can be at risk of iodine deficiency.
Calcium
Lacto-ovo-vegetarians' calcium intakes are sufficient and sometimes higher than recommended calcium amounts. On the other side, vegans' calcium intakes can vary a great deal and sometimes can be lower than recommendations. Plant-based calcium bioavailability is related to the oxalate content of foods, and phytate and fiber are the other factors which can affect bioavailability. High-oxalate vegetables (spinach, beet greens, swiss chard etc.) can't be considered as a good source of calcium even though they contain high calcium levels because absorption is not enough. When we compare them with the low-oxalate vegetables (kale, turnip greens, Chinese cabbage,etc.) these have higher absorption rates (%50). In addition to these, your body tends to lose calcium when protein, sodium and caffeine consumption is high. For provide adequate calcium intake in vegetarians and vegans, the American Dietetic Association suggests a minimum 8 portion/day of bioavailable calcium foods.
Vitamin D
If you get enough sunlight and have a normal liver function, your body can produce adequate vitamin D. But it is not possible for many people to get enough sunlight because of the urban environments and of course during the winter months. Therefore, consuming dietary sources of vitamin D may be important to provide adequate serum vitamin D levels. The main problem for vegans and vegetarians is that the major dietary sources of vitamin D are animal foods. That's why vegans and vegetarians who consume very restrictive diets are at risk of deficiency. Vitamin D supplementation is recommended if the fortified foods and sun exposure is not enough. Some experts suggest to take 1000 to 2000IU/day vitamin D or even more to provide adequate serum levels.
Vitamin B12
Vitamin B12 is only found in foods of animal origin. Vegans have increased risk for B12 deficiency if their diet is not supported by fortified products. It is suggested that vegans should have provided 3 dietary sources of B12 in their diet per day. If it is not accessible, 5-10 microgram/day of supplementation is recommended for adults (25-100 microgram/day has been used to provide adequate B12 level in older people).
I can say that there more negative sides of vegan diets when compared with vegetarian diets. But I think you don't have to stop eating meat completely if you're not ready for that. You can make little changes in your diet and prefer to eat meat less ( of course with a healthy cooking method) and eat vegetables, fruits, whole grains etc. more. By the way, don't forget to do some physical activity :).
Bibliography:
1.Temple, N. J., Wilson, T., & Bray, G. A. (2017). Nutrition Guide for Physicians and Related Healthcare Professionals. Cham: Springer International Publishing. doi: 10.1007/978-3-319-49929-1_20
2.Versanto, M., Winston, C., & Levin, S. (2016). Position of the Academy of Nutrition and Dietetics: Vegetarian Diets. Journal of the Academy of Nutrition and Dietetics,116(12), 1970-1980. doi:10.1016/j.jand.2015.02.033
Plant-based diets have a role in decreasing the risk of chronic diseases like cardiovascular disease(CVD), cancer, and type 2 diabetes. The American Institute for Cancer Research promotes a plant-based diet which means you should get two-thirds of your food intake from vegetables, fruits, whole grains and beans. In the latest American Dietary Guidelines(2015-2020), vegetarian diets are suggested as one of the healthiest dietary patterns. But you should be careful! Because the adaptation of vegetarian diets can cause some nutrient deficiencies, however, these can be prevented with a proper diet plan. If a vegetarian diet is balanced, it will be rich in dietary fiber, complex carbohydrate, n-6 fatty acids, folate, magnesium, vitamin C and E. On the other hand, conversely to a Mediterranian or omnivorous diet, vegetarian diets, especially vegan ones, are prone to being lower in protein, n-3 fatty acids, zinc, calcium, vitamin A and B12. That's because these diets lack red meat, animal protein and/or dairy products.
Protein
Plant origin proteins have lower biological values than animal origin protein and it is in a less usable form. But vegetarian and vegan diets provide enough protein intake when the energy intake is adequate. When you eat a variety of plant foods( soy protein, textured vegetable protein, legumes, nuts, seeds and grains..) during the day, it gives you all essential amino acids which you need, if the calories in the diet are enough. Continuous intake of soy products and legumes will supply enough protein intake for vegetarians and also provide other indispensable nutrients.
Vegetarian and vegan diets might be low in n-3 fatty acids(alpha-linolenic acid), especially marine source fatty acids (eicosapentaenoic acid(EPA), docosahexaenoic acid(DHA)) and high in n-6 fatty acids(linoleic acid). Plant-based n-3 fatty acid can be converted to EPA and DHA, but it is not enough and conversion can be inhibited by high consumption of n-6 fatty acids. For the maintenance of immune, cognitive and cardiac function, these long-chain fatty acids are important. You can consume plant-based n-3 fatty acid sources (flax, chia, canola and hemp seed, walnuts and their oils) and supplements to provide adequate n-3 fatty acid levels.
Iron
In a recent study, it was found that iron absorption differs from %1 to %23 depending on three sets of factors: iron status, inhibitors, and enhancers. It might surprise you to learn that vegetarians consume as much or maybe a bit more iron than omnivores, although vegetarians have lower iron stores when compared with nonvegetarians. We should know that a person's iron status can be influenced by physiological needs and that iron stores can affect iron absorption. Plant-based foods include non-heme iron and this is more easily affected by inhibitors (phytates, soy protein, polyphenols and tannins). If you are a vegetarian, don't drink tea or coffee just before or just after a meal! Also absorption of non-heme iron can be enhanced up to10 times if the person is iron deficient. You can increase your iron absorption by moderating your diet if you have low iron status. Iron absorption can be increased by consuming enhancers such as ascorbic acid with your meal. Include parsley or kiwi fruit or an orange with your meal, for example. In general, vegetarians should aim for roughly double the iron intake of non-vegetarians.
Zinc
The great majority of zinc sources are found in animal products. Plant replacement zinc sources are legumes, whole grains, nuts and seeds (admissible source). Besides, zinc bioavailability is decreased by high levels of calcium supplementation and phytate (found in legumes, whole grains, nuts and seeds).Studies show us that vegetarians' zinc intakes are a little lower than nonvegetarians and they have lower serum zinc concentrations but still usually in the range. Sproutıng beans or legumes increases zinc levels and zinc absorption as does adding ascorbic acid.
IodineVegans can have iodine deficiencies because plant-based diets can lack iodine. If key vegan iodine sources (iodized salt or sea vegetables) are not consumed by vegans, they can be at risk of iodine deficiency.
Calcium
Lacto-ovo-vegetarians' calcium intakes are sufficient and sometimes higher than recommended calcium amounts. On the other side, vegans' calcium intakes can vary a great deal and sometimes can be lower than recommendations. Plant-based calcium bioavailability is related to the oxalate content of foods, and phytate and fiber are the other factors which can affect bioavailability. High-oxalate vegetables (spinach, beet greens, swiss chard etc.) can't be considered as a good source of calcium even though they contain high calcium levels because absorption is not enough. When we compare them with the low-oxalate vegetables (kale, turnip greens, Chinese cabbage,etc.) these have higher absorption rates (%50). In addition to these, your body tends to lose calcium when protein, sodium and caffeine consumption is high. For provide adequate calcium intake in vegetarians and vegans, the American Dietetic Association suggests a minimum 8 portion/day of bioavailable calcium foods.
Vitamin D
If you get enough sunlight and have a normal liver function, your body can produce adequate vitamin D. But it is not possible for many people to get enough sunlight because of the urban environments and of course during the winter months. Therefore, consuming dietary sources of vitamin D may be important to provide adequate serum vitamin D levels. The main problem for vegans and vegetarians is that the major dietary sources of vitamin D are animal foods. That's why vegans and vegetarians who consume very restrictive diets are at risk of deficiency. Vitamin D supplementation is recommended if the fortified foods and sun exposure is not enough. Some experts suggest to take 1000 to 2000IU/day vitamin D or even more to provide adequate serum levels.
Vitamin B12
Vitamin B12 is only found in foods of animal origin. Vegans have increased risk for B12 deficiency if their diet is not supported by fortified products. It is suggested that vegans should have provided 3 dietary sources of B12 in their diet per day. If it is not accessible, 5-10 microgram/day of supplementation is recommended for adults (25-100 microgram/day has been used to provide adequate B12 level in older people).
I can say that there more negative sides of vegan diets when compared with vegetarian diets. But I think you don't have to stop eating meat completely if you're not ready for that. You can make little changes in your diet and prefer to eat meat less ( of course with a healthy cooking method) and eat vegetables, fruits, whole grains etc. more. By the way, don't forget to do some physical activity :).
Bibliography:
1.Temple, N. J., Wilson, T., & Bray, G. A. (2017). Nutrition Guide for Physicians and Related Healthcare Professionals. Cham: Springer International Publishing. doi: 10.1007/978-3-319-49929-1_20
2.Versanto, M., Winston, C., & Levin, S. (2016). Position of the Academy of Nutrition and Dietetics: Vegetarian Diets. Journal of the Academy of Nutrition and Dietetics,116(12), 1970-1980. doi:10.1016/j.jand.2015.02.033
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