What is fat?
Fats, known chemically as the molecules triesters of glycerol (triglycerides) and fatty acids, are one of the three macronutrients (fats, carbohydrates, proteins). Fat is vital for body processes such as digestion, transport, conversion, and energy extraction. It’s our body’s primary source for stored energy, and by weight, it contains three times the amount of energy provided by glucose which must be provided to the brain in a continuous supply throughout the day. We can’t survive without fat.
Fat is necessary for many reasons.
Digestion – Fat is not soluble in blood, so bile acids produced from cholesterol in the liver emulsify it along the way to make it bioavailable. It stores the fat soluble vitamins A, D, E, and K in the liver and fatty tissues. Because fat needs to be broken down through multiple processes that include the stomach, duodenum, liver, gall bladder, pancreas, and small intestine, it stays around for a long time and keeps you satiated.
Transport – Fat is part of every cell membrane in the body. It helps transport nutrients and metabolites across cell membranes.
Conversion – Your body utilizes fat for everything from activating hormones to building immune function.
Energy extraction – Between meals or when glucose is not available, triglycerides are broken down and metabolized for energy, which in times of great need, the brain’s neurons can utilize.
Nervous system – The axon is the part of a nerve (neuron) that transmits electrical signals from the brain throughout the body to initiate all functions. The axon’s protective coating is the myelin sheath and is made of 80% lipids (fats) that must be provided by the diet.
What‘s the difference between brown fat and white fat?
Brown fat is abundant with mitochondria, which give it the rich brownish red color. Mitochondria’s function is respiration and energy production. It produces ATP (adenosine triphosphate) by using the energy stored in food, in this case, fat. Brown fat burns calorie-intense lipids, releases stored energy and creates heat.
White fat stores lipids but doesn’t burn them, creating unhealthy belly fat. This is the type of fat that makes people “fat”. When too much white fat is accumulated, we gain the wrong kind of weight. Subcutaneous fat like the kind that’s been stored around the belly, thighs, or butt can’t be burned without new dietary fat, which triggers fat-burning channels through the liver.
These fats are solid at room temperature, given their carbon chain. Most of them are long chain fatty acids. Dairy fats are saturated fats and often ridiculed. But if one is careful enough to choose milk obtained from grass fed cows and not cattle fed on grains and corn, as these fats are healthier.
Saturated oils like coconut oils are in fact more beneficial for someone suffering from a liver disease or kidney disease as they are medium chain fatty acids and are assimilated well in the body’s digestive system. Saturated fats like red meat, egg yolk, butter should be had very sparingly.
Unsaturated – Monounsaturated fats:
There are two kinds of unsaturated fats- monounsaturated and polyunsaturated, depending on the bonds their carbon atoms have. Mostly all cooking oils are unsaturated fats. When it comes to choosing the right oil it is essential to consider the ratio of mono to polyunsaturated fats present in the oil. Monounsaturated oils are more stable and hence oxidize very slowly in the body. Oils like rice bran oil, olive oil and groundnut oils are monounsaturated. They have properties, which can lower the total cholesterol and increase the HDL-the good cholesterol.
Fats are an essential part of our body’s metabolism. So, understand their different forms and incorporate them in your daily diets accordingly. Also, at the end of the day, a good fat is also a fat, carrying the same amount of calories. For example, 1 tablespoon of fat is 100 calories approximately. It is the rate of digestion, the assimilation and processing of these fats in the body that determine our cholesterol, our adipose tissue- the fat stored in the tissues. So consider creating a balance by using the right kinds of fats in the right proportion.