Are All Fats Unhealthy?
No! Some fats are essential to our health. The reason that fats have a bad name is because certain fats (saturated fats) are a major cause of coronary heart disease. But this does not mean that all fats are bad.
So Which Fats are Good?
Fats fall into two categories:
- Saturated Fats
- Unsaturated Fats
Note: There is a third ‘hybrid’ category of fats, called Trans-fats (or hydrogenated fats). Typically, these are unsaturated fats used in food manufacturing processes in which they are ‘cooked’ and turned into saturated fats. Found mainly in margarines and shortenings, these trans-fats are especially unhealthy.
Saturated fats come from animal foods (meat, cheese, eggs, dairy) and a few oils like palm kernel oil. These fats are not essential to health – in fact, if consumed in excess, they can be difficult to metabolise (causing weight gain) and may lead to narrowing of the arteries (causing heart disease).
These include Mono-unsaturated fats and Poly-unsaturated fats.
Mono-unsaturated fat is considered to be one of the healthiest types of general fat. It is found mainly in olive oil, rapeseed oil, canola oil, nuts and seeds.
The high consumption of olive oil in Mediterranean countries is considered to be one of the reasons why these countries have lower levels of heart disease. This is because mono-unsaturated fat helps reduce harmful low-density lipoproteins (LDLs) which can cause blocked arteries.
Although much healthier than saturated fat, poly-unsaturated fat is considered to be less healthy than mono-unsaturated fat. This is because research indicates it may reduce the protective high-density lipoproteins (HDLs) as well as the harmful low-density lipoproteins (LDLs). However, within the polyunsaturated fats group are two very important essential fatty acids (EFAs):
- Omega 6 Fatty Acids (e.g. linoleic acid)
Found in unrefined safflower, corn, sesame and sunflower oils
- Omega 3 Fatty Acids (e.g. alpha-linolenic acid)
Found in oily fish, linseed or flax oil, hemp oil, soybean oil, pumpkin seeds, walnuts, dark green vegetables
Both these essential fatty acids are vital for good health. They regulate mental health, growth and vitality and are believed to assist the transport and uptake of oxygen throughout the body. EFA deficiency is associated with cardiovascular disease, cancer, diabetes, multiple sclerosis and other degenerative conditions.
Balance between Omega 6 and Omega 3
The optimum balance between these two EFAs in our diet is considered to be three omega 6 to one omega 3. This contrasts with the current balance in the average Western diet of 10 or 20-1 in favor of omega 6. i.e. eat more omega 3.
EFAs are Easily Destroyed
Light, air and heat destroy EFAs, so processing and packaging methods are extremely important. Ideally, when buying oils, choose mechanically processed, organic oils in opaque glass containers.
Fats, Oils, Calories & Weight Loss
Fat contains is twice as calorie-dense (1 gram = 9 calories) than carbohydrates or protein (1 gram = 4 calories). Also, all oils – no matter how healthy – are high in calories (1 tbsp = 120 calories). In addition, many processed foods and fast foods are high in fat, especially saturated fat. So for the sake of your health, become a fat-detective and reduce your total fat consumption.
For a concise explanation of how ALL surplus calories (from fats, protein AND carbs) are converted to body fat and stored as adipose tissue, see How We Gain Body Fat?
Some Practical Conclusions
- Reduce total fat consumption to 15-30 per cent of total daily calorie intake.
- Aim to restrict or (best) eliminate saturated fat consumption.
- If buying margarine, choose brands without trans-fats or hydrogenated fats.
- Aim to eat most of your fat from foods or unrefined, organic oils, rich in EFAs – especially omega 3.
- If buying oil, ideally choose mechanically pressed, unrefined, organic oils in opaque glass containers.
- If trying to lose weight, be aware that all oils are high in calories, and should be consumed sparingly.