One big misconception about healthy eating

There is a big misconception about healthy eating – lots of people believe that it means eating vegetables only. But it’s not true. Healthy eating means eating a variety of foods that give you the nutrients you need to maintain your health, feel good, and have energy. It also means getting the number of calories that’s right for you – not too much or too little.

A healthy diet protects you against many chronic diseases, such as heart disease, diabetes and cancer. Eating a variety of foods and consuming less salt, sugars and saturated and industrially-produced trans-fats, are essential for healthy diet.

Nutrients of concern for vegans and vegetarians

The nutrients of concern for vegans are: proteins, omega-3 fatty acids, cholesterol, iron, zinc, calcium, and vitamin B12. All vegans need to plan the composition of their nutrition with due care. Adding various kinds of nutrient-dense nuts, seeds, grains, and dried fruits makes a significant contribution to a vegan diet because each kind of them offers different dietary benefits to meet requirements for important nutrients – apart from vitamin B12.

Essential amino acids from proteins

Essential amino acids cannot be made by our body. As a result, they must come from food. The 9 essential amino acids are: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.

Vegetarians and vegans can maintain a high-protein diet but they have to keep 2 things in mind:

1. They will have a low level of the following essential amino acids: lysine, methionine, isoleucine, threonine and tryptophan. Of these, lysine appears to be the most commonly absent one.
2. Due to the lower protein density in plant-based foods they have to consume a larger absolute volume of food compared to a non-vegan diet. In fact, vegans must consume a lot more food to get a lot of protein.

Fortunately for vegans and vegetarians, soy beans and quinoa are known as complete proteins because they each contain all the essential amino acids in amounts that meet human requirements.

Omega-3 fatty acids

There are three Omega-3 fatty acids: alpha-linolenic acid (ALA) from plant sources, and other two – eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) – from animal sources.

• The health benefits of omega-3 fatty acids are mostly linked to EPA and DHA.
• EPA and DHA of animal origin are “ready-made” and can be utilized immediately.
• ALA of plant origin has to be converted in the body to EPA and DHA but the conversion rate is very low.

Vitamin B12

B12 is an exceptional, unique vitamin. This vitamin is of vital importance for us because it is involved in the metabolism of every cell of the human body. It plays a key role in the normal functioning of our brain and nervous system, the red blood cells formation, DNA synthesis, fatty acid and amino acid metabolism.

No fungi, plants, animals or humans are capable of producing vitamin B12. Only bacteria and archaea have the enzymes needed for its synthesis. Animals must obtain vitamin B12 directly or indirectly from bacteria and we obtain B12 from animals.

Vegetarians and vegans are unable to obtain B12 from their diet. They develop B12 deficiency regardless of demographic characteristics, place of residency, age, or type of vegetarian diet. Daily value of vitamin B12 is 2.4 micrograms for average adults. It is of utmost importance that vegans ensure they have an adequate intake of B12. But there are only two sources of vitamin B12 for them: foods fortified with B12 and supplements.

Iron

Iron from plant foods is absorbed less well by the body than from animal foods. The bioavailability of iron is approximately 5% to 12% from vegan diets, which is very low. Firstly the form of iron found in plant foods is non heme which is generally poorly absorbed in the gut compared to heme iron from animal sources. Secondly, spinach (the richest vegan source of iron) has very high levels of oxalic acid that binds iron. Also, tannins in tea and coffee and phytates in wholegrains inhibit the absorption of iron

Calcium

Calcium bioavailability from plant foods is very low. To get your recommended daily value of calcium you have to eat as much leafy greens as a cow. Calcium absorption is improved in the presence of vitamin D but is reduced by sodium and caffeine.

Let’s wrap it up

Vegans do not consume animal products, not only meat but also eggs, dairy products and other animal-derived substances. Vegan diets tend to be higher in dietary fiber, magnesium, folic acid, vitamin C, vitamin E, iron and phytochemicals and lower in dietary energy, saturated fat, cholesterol, long-chain omega-3 fatty acids, vitamin D, calcium, zinc and vitamin B12. That is why some nutrients are of great concern for vegans and vegetarians.