Wednesday, May 28, 2008

Essential fats

If you have been doggedly avoiding fat in an attempt to lose weight — this approach is WRONG. You need fats in your diet. Your brain consists mostly of fat, and your intelligence, heartbeat and muscular movements all depend on it. The only way in which your body can send electrical messages through living tissue is via your nerve cells and their connectors, which again are made of fat.

The fact is that some fats (known as lipids) are essential. They act as the second energy reserve behind glycogen, providing most of their energy at around 70 per cent of maximum heart rate. Endurance athletes utilize fat as an energy source more than other sports people and this is why they tend to be lean.

Fats are not just for energy, though. Their many other functions include insulating important organs, carrying fat-soluble vitamins and regulating hormone levels. If you're a female athlete and you experience a loss of your periods, this may be due to extremely low body fat, for this plays a vital role in the activation of the female hormone oestrogen.

Fats also contribute to health in many other ways — provided they are of the right kind. In an attempt to warn people about the risk of consuming toomuch fat, certain groups have created the impression that all fats are bad, but this simply is not true.

Diet Start

Are you eating the wrong fats?

Many people in the Western world are getting 45 per cent of their calorific intake from fats, but these are junk fats that the body cannot use, so these people are just as fat-deficient as those on extremely low-fat regimes.

THERE ARE TWO MAIN TYPES OF NATURAL FATS:

1. Saturated fats come primarily from animal sources such as meat and dairy products, and from coconut and palm-kernel oil; they are solid at room temperature. They provide the body with a stored form of energy in fat cells.

2. Unsaturated fats are found in vegetables, nuts, grains and seeds, and in fish and game; they are liquid at room temperature. They contain two fatty acids that are essential to life and, more importantly, that the body cannot produce itself. These are linoleic acid (omega-6) and linolenic acid (omega-3) From these two 'essential fatty acids' your body can make all the other fatty acids it needs.

Is it just a case of cutting out saturated fat?

Saturated fat gets a bad press, and a diet too heavy in it has been closely linked to cardiovascular disease. However, there is another fat with an equal capacity to harm: hydrogenated fat.

Hydrogenated fat is solid or semi-solid at room temperature (the best example being margarine). It is created when a liquid oil (such as corn oil) has hydrogen added to it, changing its chemical structure. This in turn can interfere with the metabolism of some essential fatty acids. Research has shown that the trans fats in hydrogenated fats can increase LDL (poor) cholesterol,decrease HDL (good) cholesterol and thus raise the risk of coronary heart disease. Hydrogenated fat is found in almost all processed foods, plus frozen convenience foods and deep-fried fast food. This is another good reason to say goodbye to junk food and hello to fresh produce.

If you usually ingest high amounts of processed fats and use commercially altered oils for cooking, then you are certainly not getting the balance of fats that your body needs.

Why don't food manufacturers use healthier oils?

Even though the food industry uses vegetable oils that contain a reasonable amount of omega-6 fatty acids, they avoid omega-3s because these are more susceptible to oxidization — in other words, they go rancid quickly and don't have a long shelf life.

Ironic, isn't it? Food manufacturers quite happily promote food under the guise of lowering cholesterol and reducing heart disease, but they are ignoring one of the fats essential to health. So unless you are eating high amounts of fish, fish oils, leafy vegetables, nuts, unrefined olive oil, tofu or flaxseed oil, your ratio of omega-6 to omega-3 fats is probably screwed up, and this in turn will be screwing up your health.

The current Western diet is much higher in omega-6 fatty acids than omega-3's. Remember those healthy Palaeolithic people we were discussing earlier? They were eating equal amounts of both.

How is this relevant to body weight?

If you are eating a diet with a good balance of omega-6 and omega-3 fatty acids, this will affect your body in beneficial fat-burning ways:

  • Your metabolic rate will be increased, as will the metabolism of fats, so more stored fat will be burned for energy
  • Your cells' sensitivity to insulin will be increased, so that it regulates blood- sugar levels more effectively
  • The ratio of insulin to glucagons will improve, which will unlock the fat- storage banks and again allow fat to be burned as energy
  • Natural appetite suppressants will kick in.

So if you want to improve your chances of losing weight, you need to up your intake of omega-3 and other healthy fats.

Essential fats Q&A

Q. How often should I eat oily fish per week if I want to consume enough omega-3 fatty acids?

A. You should aim to eat oily fish a minimum of 2-3 times per week, or ensure you use flaxseed oil regularly on salads to raise your levels. Try to eat fish from as safe a source as possible as many coldwater fish are contaminated with heavy metals and pesticides.

Q. How can I avoid hydrogenated fat?

A. Cut out processed food and only use cold-pressed un-refined oils such as olive oil, or coconut oil for cooking. Don't eat fast food that has been deep-fried and avoid butter type spreads. If you did this, then you should be able to avoid consuming dangerous trans fatty acids.

... andjoyohoxing