Fat is an important dense source of energy and helps to absorb fat-soluble vitamins. But which fats should we consume?
Bad Dietary Fat
Science-based health recommendations state that trans fat, saturated fat and cholesterol are not required in the diet. In particular, trans fat (look out for “partially hydrogenated oils” on the nutrition label) and saturated fat are best avoided as much as possible whereas they clog our arteries, and increase the risk of heart attack and death. A diet low in cholesterol is also preferable, as it may prevent cardiovascular diseases and possibly reduce the risk of several cancers.
Cholesterol is only found in animal products. Trans fat and saturated fat are generally found in cakes, cookies, pies, pastries, bread, fast food, restaurant food, or any product that contains margarine, cheese, meat and dairy.
The Types Of Fat We Should Consume
We do require some essential fatty acids in our diet, which cannot be made by our body itself. These essential fatty acids are the omega-3s and omega-6s, referring to two groups of fatty acids, each with a characteristic structure.
When we speak of omega-3, we generally refer to one specific type of omega-3 named alpha-linolenic acid, or ALA. This is the main type of omega-3 fatty acid which we consume through our diet, good for our cardiovascular system and our overall health. For example, replacing saturated fatty acids with omega-3s significantly reduces cardiovascular disease risk. ALA can be converted into other omega-3-type fatty acids, like EPA and DHA. Although ALA, EPA and DHA are all omega-3s, there are separate recommendations for the intake of ALA on the one hand, and for EPA and DHA on the other hand. Reason is that only a small percentage of ALA is converted into EPA and DHA, and they may have different biological function.
Adequate ALA intake is suggested to be at least 0.5% of our total calorie intake. In addition, an intake of 250 mg per day of EPA/DHA is suggested for healthy adults.
What about the other essential fatty acid, omega-6? The omega-6-type fatty acids are generally more linked to inflammation, compared to the omega-3-types. Omega-3s and omega-6s compete for the same enzymes for their conversion, and it is therefore suggested that consuming too much omega-6s may reduce the good effects of omega-3s. Excessive amounts of omega-6s, as generally found in today’s diets in the form of seeds and vegetable oils, have been linked to the disease progression of cardiovascular disease, cancer, and inflammatory and autoimmune diseases. So, although we need some omega-6s in our diet, there is no daily recommended intake established for omega-6s.
Omega-3 Containing Foods
ALA is present in flaxseed, but also chia seeds, hemp seeds and walnuts. So in daily life, the recommended ALA intake will look something like 1 tablespoon of milled flaxseed per day. All these foods come with the needed omega-6s as well.
EPA and DHA are mainly made by microalgae. That is also where fish get their omega-3s from, the consumption of algae. Although that would make fish a great source of healthy omega-3s, a number of studies have shown the presence of pollutants in fish (wild and farmed) which can be a health risk for consumers. We could however get EPA and DHA pollutant free straight from the source, as an algae-derived daily supplement of 250 mg EPA/DHA.
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