Having spoken with countless number of forward-thinking nutritionists, doctors and wellness professionals in recent months, I can tell you one thing for sure: while most agree that we all have our own unique body chemistry, they have differing views on what types of fat and how much of them we should be consuming. Many still favor a more plant-based approach with moderates amount of vegetable fat, while others go for a paleo-style diet that cuts out sugar, reduces carbs and increases animal protein intake. Some will even go as far as going ketogenic and promote a regimen that includes high daily fat consumption.
However, there is one belief most experts share: avoid processed foods. And where fat is concerned, that pretty much means we should not be eating lipids our bodies don’t recognize. In this article, we will explore what the different types of fats are, how they work, and which ones our bodies can and cannot handle.
What lipids does the body recognize?
Our bodies should be able to metabolize fats and oils that come from nature. Biomolecules like fatty acids, cholesterol and DNA twist into certain shapes or configurations to ease their interaction with each other and water. Processing a fatty acid – for example in vegetable oils – can change its shape. This is problematic for our enzymes because they pick them up and can’t let go of them, causing problems at a cellular level and eventually killing the cells. The cumulative effect of consuming processed fats over time can really disrupt basic functions like your metabolism, circulation and immunity.
Lipids, heat and oxidization
Different fats oxidize more or less easily with heat, and this can distort their configuration, making them toxic. Here is a quick explanation on how fats behave in heat.
Saturated fats – like coconut oil, butter or ghee – are solid and don’t easily become rancid when heated. They have a shape that don’t make room for oxygen to squeeze in, so even when they are heated, oxygen will stay out of those molecules. Notice I don’t mention cholesterol being a problem: the jury is still out on that. While an increasing number of studies prove cholesterol is not the cause of heart disease, many prove the contrary. For now, let’s just say that butter is better than canola oil. More on that below, under the polyunsaturated fat section.
Monosaturated oils – like olive oil – are relatively stable and can be used for cooking. They have room for one oxygen molecule, which also makes it hard for oxygen molecules to get in.
Polyunsaturated fats (PUFAs) – like canola and sunflower oil – however, are very fragile. They can develop harmful free radicals when subjected to heat and oxygen. Because they have two molecules (double bonds), they are more than a million times more likely to bind with oxygen. Typical sources of polyunsaturated fats include most nut and seed oils, which we tend to think are healthy; and to a degree, they are. The oil you consume when eating actual sunflower seeds is healthy: the human body has the enzymes necessary to oxidize these these PUFAs and convert them into a safer compound. However, heat needs to be used to extract oil out of their seeds and this “refining” process converts them into distorted molecules, making them toxic. If you cook with them, it becomes even worst. Scientists have found that “heating up vegetable oils led to the release of high concentrations of chemicals called aldehydes, which have been linked to illnesses including cancer, heart disease and dementia.” In an experiment conducted by a team at De Montfort University Leicester (DMU), it was found that sunflower and corn oil produced aldehydes at levels 20 times higher than recommended by the World Health Organisation. Olive oil, butter and goose fat produce far less aldehydes.
Transfats – like margarine – these are already toxic as is, so definitely don’t use them in cooking. Artificial trans fatty acids (transfats) are produced when hydrogen is added to liquid vegetable oils to make them solid. You often see this in product labels as “partially hydrogenated oils”. This is old news, even the U.S. Food and Drug Administration came to this conclusion in 2015, when it said that “partially hydrogenated oils (PHOs), the primary dietary source of artificial trans fat in processed foods, are not “generally recognized as safe” or GRAS for use in human food.” It gave companies 3 years to discontinue their use.
Omega 3 vs Omega 6
Omega-3 and omega-6 are two types of PUFAs. They are both required for the body but ideally, you want to have a higher ration of Omega 3 in your diet than Omega 6. Omega 3 is anti-inflammatory and Omega 6 is inflammatory. Unfortunately, our western diets tend to be too high in omega-6 fatty acids (present in large amounts in refined vegetable oils). So when choosing a fat, it’s always best to use one that has a lower Omega 6 : 3 ratio.
What fats are “safe”?
There are lot of different charts out there that can give you an indication of which ones you should use and those you should avoid, but here is one I found in Dr. Catherine Shanahan’s book Deep Nutrition which I find relatively easy to understand. The Good Fats column also contains the ones with the better Omega 6 : Omega 3 ratios. Keep in mind that all animal products should come from grass fed, organic fed animals, otherwise best to stick to the vegetable sources.
When I saw this list and started reading labels, I realized a lot of “healthy” ,”paleo” ,”dairy free” and “gluten free” products use bad fats. In fact, most do. So, as much as possible, try buying and consuming whole foods, I like to think that nature doesn’t make bad fats.
Notes on this chart:
- Ghee (clarified butter) has a higher smoking point than butter, so if you are going fry anything, opt for ghee, which also has less lactose. However, when buying Ghee, get desi ghee, not vanaspati ghee, which is hydrogenated. It is also very easy to make yourself at home using grass fed butter.
- Some of you may be familiar with other animal fats like duck and goose. These would fall in the Good Fats category.
