Choosing the right fats

The dock

For decades fats are accused of all evils, and in particular cause or at least increase the risk of cardiovascular disease ... and this wrongly. The confusion comes from the discovery of cholesterol found in atherosclerotic plaques (plaques that clog arteries come). Want to reduce fat however, is not a good idea if you want to reduce the cardiovascular risk, quite the contrary. Eat dry, nonfat, increases cardiovascular risk. We now know that some fats are protective and others rather harmful.

Fear of fat

Eating fat: avoid absolutely. This attitude leads to excessive carbohydrate diet, which it is deleterious. Removing visible fat, including vegetable oils, that is to say, the good fats, there are only invisible fat, mostly animal fats that can be atherogenic (coming clog arteries). In 2010, in France, the Recommended Dietary fat increased from 30-35% to 35-40% of total caloric intake, further evidence that they are necessary for good health.

Eat more fat and less carbs for better health

Certain dietary patterns can be very high in fat and yet very protective cardiovascular level, for example the case of the Eskimo diet. One study even showed that a high fat (59% of calories as fat) and low-carb diet is more protective than a conventional system providing carbohydrate [1]. Increasing fat and reducing carbohydrate food intake, blood lipid parameters all subjects were improved (see list of foods and their carb).

Reducing carbohydrates

Why reduce carbs? Because a diet too rich in carbohydrates increases the production of triglycerides (TAG), but also increases the amount of small dense LDL, the most atherogenic lipoprotein of this type [2]. A reduction of the glycemic index of foods and the total amount of carbohydrates lowers the proportion of this subclass of LDL [3] and thus reduce cardiovascular risk.

Increase lipid

Why have greater fat intake? Firstly it must be replaced by another macronutrient carbohydrates, and it is not necessary to increase protein too. Secondly, because fat can be protective. It is known that the essential fatty acids (omega-3 and omega-6) are the source of the formation of prostaglandins, which have major roles in the biological organism. Omega 6 series is the basis for the formation of PGE1, anti-inflammatory prostaglandin, but also later in the chain of PGE2, very inflammatory prostaglandin, increasing vessel contraction and coagulation. Conversely the omega 3 series allows the synthesis of the chain end PGE3, highly anti-inflammatory prostaglandin, decreasing platelet aggregation and vasoconstriction. We see here how bad ratio between the 2 series may increase cardiovascular risk. Furthermore, the two series are competing because they use the same enzyme; for example, too much omega 6 penalizes the formation of prostaglandin PGE3 by omega 3. The total intake of essential fatty acids is important, but it is mainly the ratio of omega 6 / omega 3, which is essential for cardiovascular protection.

It is therefore to have a qualitative rather than quantitative approach.

Fat: a matter of choice

How to reduce cardiovascular risk? Choosing the right fats:

The majority of fat intake should be from monounsaturated fats: olive oil, almonds, avocados, poultry ... (see list of foods rich in monounsaturated FA). This lowers LDL, known as "bad cholesterol." Decrease saturated for the same reason fatty acids (see list of foods and their composition in saturated fatty acids). Care should be taken to increase the intake of omega 3, which is often too low (fatty fish, walnuts and walnut oil, rapeseed oil), while reducing sources of omega 6 (food and processed foods, oils sunflower, corn, grape seed and soy). In addition, omega-6 decreased HDL, known as "good cholesterol"; another good reason to limit them. Another type of fat to avoid: Trans fatty acids. These are obtained by an industrial process, hydrogenation, which allows the manufacture of margarines solids from liquid oils. These fats are definitely the most dangerous to health. It is therefore necessary to choose a non-hydrogenated margarine, and rich in omega 3. Although it should choose fats wisely, it finally makes sense not to reduce or to increase at the expense of carbohydrates.