YOUR BODY NEEDS FATS

With the current preoccupation with obesity and overweight, fats are being considered as something to avoid. However, don’t completely cut out fats from your diet. They play an important role in keeping the body healthy. 

Why fats are important…

FATS…

• provide energy for all body functions, and are a reserve of energy when stored in the body.

• support health  

                    - transport some fat soluble vitamins 

                    - regulate body cholesterol metabolism. 

                    - insulate against extreme temperatures 

                    - protect organs from injury. 

                    - help the body to use proteins and carbohydrates more efficiently.

• make food very tasty

Fats are required to keep the body healthy but the type and amount of fat in the diet depends on tradition, culture, and economic factors .For example, the traditional Japanese diet is low in fat, whereas Italian food uses a lot of olive oil. Coconut oil is used in Kerala while mustard oil is used in Bengal and some northern states.

The body breaks down fats and oils in the diet into fatty acids.

UNDERSTANDING   FATTY ACIDS…

Fatty acids can be saturated, monounsaturated or polyunsaturated.

Fats with a high content of saturated fatty acids are solid at room temperature and are usually obtained from animal sources, for example, lard, suet and butter.

Trans fats which are also solid at room temperature enhance the flavour, texture, and shelf life of many processed foods but they are a health risk.Small amounts of trans fats occur naturally in beef, lamb, and full-fat dairy products but most are commercially produced by processing liquid vegetable oil into a solid fat –  for example Vanaspathi/ Dalda/margarine. Major sources of trans fatty acids are  pizzas, cakes, cookies , doughnuts,  crackers, meat and dairy products, snack chips, peanut butter and shortening in fried foods.

Like saturated fats, trans fats raise LDL "bad" cholesterol and increase the risk of heart disease. But unlike saturated fats, trans fats lower HDL "good" cholesterol and may do more damage. So the intake of these foods should be very controlled.

Most plant oils,except for palm oil and coconut oil, are high in either polyunsaturated (PUFA) or monounsaturated fats (MUFA). Monounsaturated fats should be used as much as possible along with polyunsaturated fats instead of the bad saturated fats and trans fats.

Good sources of monounsaturated fats are olive oil, peanut oil, gingelly oil, canola oil, avocado, and most nuts.

While saturated fats and monounsaturated fats can be made in the human body, the body cannot maketwo polyunsaturated fats - linoleic acid (LA)and alpha-linolenic acid(ALA). They are necessary for human health and since the body cannot make them, they have to be obtained through the diet. So, they are called essential fatty acids (EFA).Both linoleic acid (LA) and alpha- linolenic acid (ALA) can be converted in the body into other polyunsaturated fatty acids (PUFAs).

A diet low in both fat and saturated fat combined with regular fish consumption produces the best results.

ESSENTIAL FATTY ACIDS (EFAS)…

There are basically two types of EFA’s –Omega- 6 essential fatty acids and Omega -3 essential fatty acids.

Omega-3 fatty acids and Omega-6 fatty acids play a very important role in brain function as well as normal growth and development. They help stimulate skin and hair growth, maintain bone health, regulate metabolism, and maintain the reproductive system.

Most Omega-6 fatty acids in the diet come in the form of linoleic acid (LA)from vegetable oils and also from leafy vegetables, seeds, nuts,  grains and plant oils such as corn oil, unhydrogenated  soybean oil, and sunflower oil, safflower oil , olive oil as well as meat and poultry.

A well- balanced diet provides enough of it but the effectiveness is spoiled by the sugar and trans fats in the diet.

Omega-3 essential fatty acids come primarily from fatty fish such as salmon, herring, anchovies, sardines , mackerel, and tuna, as well as from nuts and seeds, soyabean, walnuts, almond, sesame seed  and flaxseed in lesser amounts. Alpha-Linolenic  acid  (ALA )is the primary member of the Omega- 3 family.

Most fats are a combination of saturated, monounsaturated and polyunsaturated fatty acids. The body’s requirement depends on an optimal ratio and a ratio of 1:5 or 1:10 of Omega-3 fatty acids to Omega-6 fatty acids has been suggested. A balanced diet that includes grains, seeds, nuts,  leafy vegetable , vegetable oils and fish supplies  a good balance of all the Omega- 3 and Omega- 6 fatty acids.

For the right balance eat more fish than meat. Even one fish meal a week can make the difference. Fish provides many minerals and vitamins. 

Fish oil supplements should be taken under the supervision of your physician.

A diet that is high in meat tends to contain 14 - 25 times more Omega-6 fatty acids than Omega-3 fatty acids. 

The Mediterranean diet has a healthier balance between omega-3 and omega-6 fatty acids as it emphasizes foods rich in omega-3 fatty acids, including whole grains, fresh fruits and vegetables, fish, olive oil, garlic, as well as moderate wine consumption.

DEFICIENCY OR IMBALANCE IN OMEGA 6 FATTY ACIDS AND OMEGA 3 FATTY ACIDS CAN AFFECT HEALTH.

Omega-3 deficiencies are linked to decreased memory and mental abilities, tingling sensation of the nerves, poor vision, increased tendency to form blood clots, weakened immune function, increased triglycerides and "bad" cholesterol (LDL) levels, impaired membrane function, hypertension, irregular heartbeat, learning disorders, menopausal discomfort, itchiness on the front of the lower leg(s), and growth retardation in infants, children, and pregnant women.

On the other hand, high doses of Omega- 3 fatty acids can cause gastro- intestinal disturbances such as abdominal discomfort, diarrhoea, nausea and belching.

Some Omega-6s improve diabetic neuropathy, rheumatoid arthritis, skin disorders (e.g. psoriasis and eczema), and aid in cancer treatment.

ARE PHYTOSTEROLS GOOD FOR PEOPLE WITH DIABETES? 

Phytosterols are cholesterol- like molecules found in all plant foods with highest concentration in vegetable oils. These are absorbed only in trace amounts but inhibit absorption of intestinal cholesterol and help lower LDL cholesterol in patients with diabetes.

TIPS TO GET THE MOST OUT OF FATS…

• High heat, light, and oxygen destroy essential fatty acids, so while consuming foods for their essential fatty acid content, try to avoid cooked or heated forms. For example, raw nuts are a better source than roasted nuts. Never re-use any type of oil.
• Heating fish? - Omega-3 fatty acids are very easily damaged by heat, light and oxygen. They become rancid and the flavour and taste change and nutritional value is lowered.  Baking or steaming fish containing Omega-3 fatty acids are better cooking methods than frying.

• Heating olive oil? –  If cooking at high temperatures, use refined olive oil and not virgin oil. The unrefined particles in virgin olive oil are burnt when heated and this spoils the flavour. Use virgin olive oil without heating in salads instead of salad oil for another healthy change.

• Replace hydrogenated fats (like margarine),cholesterol-based fats (butter/dairy products) with healthy essential fatty acid-based fats whenever possible. For example, instead of margarine or butter on your warm vegetables, use extra virgin olive oil with salt. 

• Sprinkling flaxseed powder on vegetables adds a slightly nutty taste. Whole flaxseeds are usually passed through the intestine, absorbing water only and not yielding much oil.  However, it's best not to use large amounts of flaxseed in its ground seed form, as it contains phytoestrogens. 
• Replace oily snack foods, like potato chips and corn chips, with healthy nuts and seeds.
• Vegetarians can achieve a better balance of PUFAs in their body tissues by using less sunflower, safflower and corn oils and more oils containing alphalinolenic acid such as rapeseed (canola) oil, mustard oil, peanutoil, gingelly oil, or soya bean oil. This would encourage their tissues to make more DHA.
• Although most diets supply sufficient linoleic acid, it is often not converted because of metabolic problems caused by diets rich in sugar, alcohol, or trans fats from processed foods, as well as smoking, pollution, stress, ageing, viral infections, and other illnesses such as diabetes. 

Depending only on one type of cooking oil does not guarantee that a person is getting the best combination of various fatty acids. So, use a combination of oils in rotation to get allthe benefits. While selecting cooking oils consider the omega -6 to omega -3 ratio, MUFA content, PUFA content and saturated fatty acid content. Be aware of the trans- fatty acid content and the smoking point and heat stability of cooking oils as Indian cooking involves high temperatures for long hours.The ideal oil combination for Indian population for best intake of various fatty acids is groundnut oil or gingelly oil or mustard oil used alternately with soya bean oil,sunflower oil, Saffola or canola oil.

Ref: Understand Nutrition- Eleanor Noss Whitney, Sharon Rolfes.