What fats and oils do we select that best meet our requirements? We are exposed to a variety of views about fats and oils and their contribution, through conversation, through newspaper, magazines, books, TV and the internet. Our choices, therefore, are indirectly influenced by what we hear or see. Economic considerations, tradition, taste, habits and, in some cases, offers in supermarkets and also the increasing concern about health partly influence us. Since the consumer has become health conscious, the manufacturers use this to promote their products. The trigger is the ad through which they tell us about the oils claimed benefits: ‘Rich in PUFA’, ‘Contains no cholesterol’, ‘Best oil for the heart’, ‘Light and healthy, Protect you from heart disease’ and so on. As consumers, it is important that we examine these notions we are given, the claims made in the ads but importantly, know with clarity what is good for us, regardless of what an ad says. Are these claims correct or is it misinformation? Be an ‘aware consumer’. Here is a fact sheet on fats and oils.
Understanding jargons: Cooking oils and solid fats together are referred to as fats. Fats are essential components in our diet. It gives flavour, texture, taste, palatability in addition to providing energy (9 Kcal/1g) and essential fatty acids (EFAs) to meet the body’s metabolic requirements.
Fatty acids: Fats in our diet provide a mix of three
Fatty acids: saturated (SFA), monosaturated (MUFA) and polyunsaturated (PUFA). We humans can synthesise SFA and MUFA besides obtaining them from the diet. However, we cannot synthesise two vital dietary PUFA – linoleic (LA) and alpha-linolenic acids (ALA) – commonly known as Omega 6 and Omega 3 respectively. These EFAs are indispensable and must be supplied from food.
Here, it is pertinent to highlight that the nature of oil (saturated, PUFA, etc.) should not be confused with its calorie value. All fats (oil, vanaspati, ghee, butter) provide the same number of calories (9Kcal/g). So, when a manufacturer claims that their oil is ‘light’, you must know it is NOT true.
– Also, you may have heard of trans fatty acids (TFA). TFAs are produced when vegetable oils are hydrogenated. Hence it is a result of processing. Please note. During hydrogenation, the liquid oils become solid because the ‘unsaturated’ fats in the oil are converted into saturated fats. Partial hydrogenation of polyunsaturated oils results in an increase of TFA content and hardening of fat. Do not be deluded, therefore. This is the point where health is compromised or traded off . TFA are present in hardened vegetable oils, most margarine, commercial baked foods and many fried foods. Hydrogenation is necessary to give the product a shelf life, but it is unhealthy for the body. Unfortunately Indian laws on food labelling do not cover transfats.
– Cholesterol is a crucial substance that our body needs for cell building, replenishing and hence growth and nourishment. It also plays a key role in the formation of some hormones. But our body has the capacity to synthesise (build its own) cholesterol (unlike EFAs), hence it is not an essential dietary component. It becomes a disease when we build more than we need.
– Sources of Fat: Fats that we eat or cook with such as butter, ghee, vegetable oil, vanaspati etc., is the ‘visible fat’. What should concern us is also the fat that is not visible but is present as an integral part of various foods that we eats such as cereals, pulses, milk, nuts, oilseeds, eggs, meat, etc.Though present in small amounts, this ‘invisible fat’ adds up to a substantial level in our diet and we usually remain oblivious or in denial of this component of fat. Animal foods (eggs, meat) provide high amounts of invisible fat. The most notorious fat is the fat in processed, ready-to-eat foods, packaged foods – the ‘hidden fat’
– Sources of SFAs are coconut oil, vanaspati, animal fat (ghee/butter) and animal foods (milk/milk products/meat)
– Oils from palm, groundnut, cotton seed, sesame and olives are rich in MUFA as compared to other oils
– All edible vegetable oils are rich in PUFA, but vary in their composition of EFAs (omega-6 and omega-3 fatty acids) and critically the right ratio in which they need to be present. (Omega-6 is easily found in the foods we eat, but not omega 3. Most oils contain omega-6 but not omega-3 and this is often not known to a consumer. ) While most of the vegetable oils (except coconut) contain omega-6 fatty acid, oils extracted from soyabean, rapeseed, mustard and rice bran have both omega 3 and omega 6. Legumes/pulses, mustard, fenugreek seeds and green leafy vegetables are also good sources of omega-3. Fish oil is an important source of omega-3 acids. (Covered later, again).
We can reduce both SFA and cholesterol intake by limiting the consumption of high-fat animal foods like meat, eggs, organ meats and dairy fats.
However, consumption of eggs (three eggs/week) is recommended in view of several nutritional advantages.
PHVO or partially hydrogenated vegetable oils – vanaspati, bakery fats and margarines – sources of transfats or TFA are largely used in northern India as cooking medium importantly in restaurants, canteens, delis. Major dietary sources of TFA in India are deep fried (often refried) fast foods such as samosa, pakora, baked products (biscuits), salted snacks, packed snack foods. Most of the TFA enter our diet through oils used in household cooking, restaurant, as well as deep fried fast foods (namkeens, sweets).
What about the plant foods, particularly the vegetable oils? Do they contain cholesterol? Note, vegetable oils do not contain cholesterol. Manufacturers of vegetable oils claim that their oil contains “No Cholesterol” and therefore is heart friendly, beneficial for heart patients etc., etc. As an aware consumer, you now understand that such claims are misinformation. These are competitive statements made to misguide us to think that other brands contain cholesterol and get us to prefer the advertised oil.
Health implications of different fats/fatty acids: SFA present in ghee, butter and coconut oil are easily digested and absorbed, and are considered good for infants and young children. But excessive intake of fats, especially saturated fats adversely affects the lipid profile and increase the risk of cardiovascular diseases. It is therefore recommended that saturated fat intake be restricted in adults. The intake should not exceed 8-10 per cent of daily calories.
Vegetable oil makers claim that you should use a particular vegetable oil as it has a high content of PUFA and is heart protective. Should we get carried away by this claim? Note, high content of PUFA alone is not enough, what should concern us is the appropriate balance of the two classes of PUFA (omega-6 and omega-3) in the oil and the diet. The omega-3 in the PUFA is beneficial for prevention of inflammation and accumulation of fatty material in blood vessels and clotting of blood. Omega-3 increases insulin sensitivity, glucose utilisation and decreases adiposity (fat accumulation) and hence is anti-atherogenic (prevents fat deposits on artery walls). But omega 3 can be consumed only in balance with omega 6.
Omega-6 PUFA decreases plasma cholesterol but at high intakes also decrease HDL cholesterol (the good cholesterol) putting your heart at greater risk. This has been the defect of PUFA rich oils. On a daily basis, our diets generally furnish high omega-6 level, because of its wide distribution and abundance in many common dietary fats. Omega-3, on the other hand, is present in very low levels in animal fat and common vegetable oils; hence the diet furnishes low omega-3 levels. It is therefore recommended to increase the omega-3 acid intake and reduce the quantity of omega-6 PUFA obtained from cooking oils.
A word of caution about trans fatty acids (TFA): TFA (present in vanaspati) are more harmful than saturated fats, since they not only increase bad cholesterol (LDL) but also decrease the good cholesterol (HDL). Current evidence indicates that saturated fats and a high intake of trans fatty acids may increase the risk of heart diseases. Today fast foods/street foods are becoming part of our life style. and it is estimated that 400,000 tonnes of snacks are consumed every year. So, think again, before you pick up the packet of chips and namkeen.
From practical point of view, our concern is which vegetable oil is best suited to furnish this ideal ratio. Interestingly, no single vegetable oil furnishes both ideal PUFA-SFA and ideal omega-6/omega-3 ratio. To illustrate, oils such as safflower oil, sunflower oil and soyabean oil, furnish higher than ideal PUFA-SFA ratio, but provide appropriate omega-6/omega-3 ratio. On the other hand, coconut oil provides low PUFA-SFA ratio but inadequate levels of essential fatty acids. Therefore, complete dependency on just one vegetable oil, as the sole source of fat in our diet is undesirable.
So, the wisdom lies in selecting oils which maintain the recommended ratio of omega-6 to omega-3 of 5-10 in the total diet (5:1 to a maximum of 10:1), and the ratio of PUFA/SFA of 0.8 to 1.0 in the total diet. Given that no more than 20-30 per cent of daily calorie intake of an individual should come from fat in the diet, the distribution across MUFA, PUFA and SFA should each be 8-10 per cent energy intake. Urban families are found to post far higher intakes owing to very high consumption of fat rich foods.
Choice of Cooking Oil: Use a combination of vegetable oils. There is a lot to choose from a variety of oils as highlighted here:
1. Groundnut oil or Sesame Oil or Rice Bran Oil + Mustard Oil;
2. Groundnut oil or Sesame Oil or Rice Bran Oil + Canola;
3. Groundnut oil or Sesame Oil or Rice Bran Oil + Soyabean Oil;
4. Palmolein + Soyabean oil;
5. Safflower or Sunflower oil + Palmolein + Mustard Oil
Using mustard oil in combination with other oils as highlighted above will help decrease the overall intake of erucic acid present in mustard oil.
Remember fat is important for good health. So, make a wise and healthy choice.
Also read: Case Analysis | Case Study
The writer is Professor, Discipline of Nutritional Sciences, School of Continuing Education, IGNOU, New Delhi
