Tri Oméga - Oméga-3 et tout ce qui est gras

Tri Omega - Omega-3 and everything fatty

Omega-3 fatty acids are one of several types of polyunsaturated fats; they help maintain normal blood cholesterol levels and normal heart function by reducing triglycerides and cholesterol in the blood.

Trans fats
De-stress for a moment, so I can tell you a story. We all know that if butter is left out on a hot summer day, it goes rancid. But if it is stored in the refrigerator, it is impossible to spread it without tearing the bread.....

Food industry scientists heard about this problem and came up with a solution; say hello to margarine. Made from oils such as soybean, corn or canola, it is produced by heating the oil to a high temperature and pressing it. This changes the chemical structure of the oil, which then becomes a trans fat, semi-solid when cold.

It was, of course, only years later that medical scientists linked trans fats to an increased risk of heart disease and stroke. Eating trans fats leads to an increase in the amount of low-density lipoprotein (LDL) in the blood - the bad cholesterol - and a decrease in high-density lipoprotein (HDL) - the good cholesterol. If LDL builds up in the blood, it begins to stick to the walls of blood vessels and causes constriction. When blood vessels tighten, the heart has to pump harder to circulate blood around the body, which is known as high blood pressure. If LDL continues to build up, it can cause blockage of blood vessels, leading to a stroke or heart attack.

We now know how to make spreads from "good fats", hence the abundance of cholesterol-fighting Flora and Benecol. Trans fats can still be found occasionally in frozen pies, some baked goods, frozen pizzas, and fast foods - all the things you know are bad for your health.

Saturated fats
These fats are solid at room temperature; it's the white fat visible on cold meats like bacon or rump steak, cheese, coconut oil, chocolate and full-fat dairy products. Saturated fats were often referred to as "bad fats" and even today we are encouraged to limit their intake, although today we know that not all saturated "fatty acids" are bad - some are known to be “cholesterol neutral”.

A diet high in saturated fat increases total cholesterol, which carries the same risk of high blood pressure, heart disease and stroke. Health professionals suggest that we consume no more than 20g of saturated fat per day. A meta-study on saturated fat consumption and its link to cardiovascular disease concluded that there is not enough evidence to suggest that saturated fat increases the risk of heart disease, but that replacing saturated fat by polyunsaturated fats could reduce the risk of heart disease. Other studies suggest that replacing saturated fats with polyunsaturated fats like vegetable oils or fiber-rich carbohydrates is the best way to reduce heart disease risk, but replacing saturated fats with highly processed carbohydrates could have the opposite effect.

Unsaturated fats, the good ones
Otherwise called good fats, they are mainly found in vegetables, nuts, seeds and fish, and are liquid at room temperature. There are two main categories of unsaturated fats: monounsaturated fats and polyunsaturated fats.

Monounsaturated fats: Good sources include olive oil, peanut oil, canola oil, avocados and most nuts, as well as high-oleic sunflower oils. Monounsaturated fats are one of the benefits of the “Mediterranean diet”. Despite the high fat content of this diet, the rate of heart disease in the region is relatively low. Unlike other countries like the UK and US where saturated fat consumption is high, leading to higher rates of heart disease, the main fat consumed in the Mediterranean diet is monounsaturated fat.

Polyunsaturated fats: These are essential fats; they are necessary for normal body functions and must be consumed because your body cannot make them. Polyunsaturated fats help build cell membranes and the covering of nerves, and they are necessary for blood clotting, muscle movement and inflammation. Replacing saturated fats with polyunsaturated fats or refined carbohydrates (excess sugar) reduces bad LDL cholesterol and triglycerides, and improves the total cholesterol profile.

There are two main types of polyunsaturated fats: omega-3 fatty acids and omega-6 fatty acids; both have health benefits. Good sources of omega-3 fatty acids are fatty fish like salmon, mackerel and sardines, flaxseed, walnuts, canola oil and non-hydrogenated soybean oil.

Diets rich in omega-3 fatty acids help reduce the risk of high blood pressure, heart disease and stroke. There is also evidence to suggest that they may help reduce the need for corticosteroid medications in people with arthritis. Although research has so far lacked quality, some studies link omega-3s to a wide range of other health improvements, including reducing the risk of dementia. Omega-6 fatty acids have also been linked to protection against heart disease. Foods rich in linoleic acid and other omega-6 fatty acids include vegetable oils such as soybean, sunflower, walnut and corn oils.

Omega-3s and supplements
Many of you are probably taking a fish or algae oil supplement. But do you know why? There are three more "important" forms of omega-3 fatty acids: alpha-linolenic acid (ALA), found primarily in plants, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). ), both present in foods of animal origin such as fatty fish.

The body must convert this fatty acid into EPA and DHA before it can be used for processes other than energy. The conversion is very inefficient; the rate can sometimes be as low as 5 to 10%. Plant foods containing ALA include chia, flax and hemp seeds, seed oils, nuts and soy, and green vegetables like kale and spinach.

EPA plays a role in reducing inflammation, which is beneficial in reducing the risk of many diseases. DHA has a structural role in the skin and retina of the eyes and is vital for brain development and function (which is why it is often found in fortified baby milk). DHA has shown positive effects on certain diseases such as type 2 diabetes and certain cancers. A deficiency has been associated with impaired brain function implicated in the onset of Alzheimer's disease.

Should I take an omega-3 supplement?
If you're not eating two servings of fish per week, one of which must be an oily fish, then yes, you probably would benefit from taking an omega-3 supplement. Don't rely on converting ALA to EPA and DHA from plant sources of omega-3. But still eat these foods because they are rich in nutrients. If you are pregnant or planning to be, omega-3 supplements are not recommended because they tend to contain vitamin A, which in large amounts is harmful to the fetus.