3. Main nutrients
Classification of fats
1. Saturated fats:
- Sources: animal products, coconut oil, palm oil and - fat, cocoa butter, margarine
- At most 1/3 of the composition, less is better
2. Monounsaturated fats:
- Source: Olives and olive oil, rapeseed oil, haselnuts, avocado, soya
- At least 1/3 of the composition
3. Polyunsaturated fats:
- Approx. 1/3 of the composition
- Omega-6-fatty acid (linolenic acid)
- Source: found in many vegetable oils, mostly in safflower oil, corn oil, sunflower oil
- Better reduce intake because there are many sources of it in vegan nutrition
- Omega-3-fatty acid (herbal: α-linolenic acid)
- Source: linseed oil, linseeds, rapeseed oil, walnut oil, soy oil, hempseed oil, walnuts
- Either 1 tablespoon linseed oil or 2 tablespoons rapeseed oil per day to ensure the supply of this essential fatty acid
A distinction is drawn between saturated fatty acids, monounsaturated and polyunsaturated fatty acids. Polyunsaturated fatty acids are classified into omega-6 and omega-3 fatty acids. Omega-3 fatty acids are essential for the nutrition that means they have to be provided with the food.
Vegan nutrition mostly contains constitutional unsaturated fatty acids. Omnivors however often ingest to much saturated fats which increases the risk for heart diseases and angiopathy.
The ideal composition of fatty acids in nutrition is as follows: A maximum of 1/3 saturated fatty acids, at least 1/3 monounsaturated fatty acids and 1/3 polyunsaturated fatty acids . Furthermore a supply of 0.5% omega 3 fatty acids and 2.5% omega-6 fatty acids (relating to the total energy) is recommended. Rapeseed oil has the most ideal composition of the mentioned fatty acids why it is appropriate to be the "basis oil" for cooking in general.
Omega-3 fatty acids
Where omega-6 fatty acids are to be found very often in vegan foods, omega-3 fatty acids are covered by only few vegetable foods. To guarantee to best relation between omega-6 to omega-3 fatty acids (5:1), you should choose oil with omega-3 fatty acids. The best source is linseed oil (it contains α-linolenic acid). This special oil is light sensitive and should be kept cool. It is to be used for salad and raw vegetable (never for cooking!). Also walnut oil and soy oil do contain α-linolenic acid. Walnuts and fresh kibbled linseeds cover the demand as well. The consumption of omega-6 fatty acids - found in safflower oil and corn oil - should be reduced.
To provide enough omega-3 fatty acids 1 tablespoon of lineseed oil or 2 tablespoons of rapeseed oil per day should be supplied.
Because of its negative influence on the cholesterol level (high density of lipoprotein) trans fats should be avoided. They occur in margarine, finished and deep and long fried products (mind in the declaration of ingredients "hydrogenated fats").
Which should you use?
For raw vegetables (salads etc.) use cold-pressed and unrefined:
- Linseed oil
- Rapeseed oil
- Hempseed oil
- Walnut oil
For frying / broiling:
- Rapeseed oil
- Olive oil
- High oleic sunflower oil
- Groundnut oil
- Palm oil
- Coconut oil
Essential amino acids:
- Isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, valine, histidine (only during infancy)
- Grain: rich of methionine, little lysine
- Legumes: rich of lysine, little methionine
Reference value for adults is 0,8g per day and weight.
Varied vegetarian nutrition that covers the need of energy contains all necessary essential amino acids. Especially soya (e.g. tofu), legumes (beans, lentils, peas, chick peas), wheat gluten, wholemeal foods, nuts and seed yield a high concentration of protein.
Complementary sources of protein are grain and legumes. Protein in grain is poor of lysine but contains a great amount of methionine. In turn is methionine only available in small quantities. The combination of grain products and legumes advances the quality of protein in vegan nutrition. The higher the biological valence the lower the minimum demand of protein for the organism.
Nevertheless it is not necessary to ingest different proteins (grain and legumes) at the same time to ensure the supply of essential amino acids.
- Monosaccharide: fructose, glucose (dextrose)
- Disaccharide: Saccharose (usual sugar)
- Polysaccharide: starch (digestible), fibers (indigestible)
The general recommendation to cover up 50% of the total energy with carbohydrates is easily realized with vegan nutrition. High-molecular foods in the form of starch: grain and grain products, pseudo-grain (amaranth, buckwheat, quinoa), bread and potatoes are to be preferred. Wholemeal products should be favored: they can lower the risk for diverse diseases like tumor and cardiovascular illness. Besides they provide significantly more minerals than superfine flour. Phytin acid in wholemeal products composes stable complexes with iron and zinc and blocks the absorption of other nutrients. During the sourdough leavening process or sprouted grain the bond between minerals and phytin acid is splitted.
Low-molecular sugar like fructose, glucose and saccharose are classified as carbohydrates. They may and shall have their part in nutrition in the form of fruits but should not be the only source for carbyhydrates. The reason for this is a higher risk of caries and erosion of teeth (because of too much fruit acid).