Good Fats Vs Bad Fats

There are nutritional and health dangers hidden in some polyunsaturated fats. Where does the problem lie and what can you do to protect yourself?

- Sally-Ann Creed

We now know we have been misled for decades about saturated fat being ‘deadly’ but we have also been misled about polyunsaturated fats (PUFAs). These have been promoted as everything from heart healthy to slimming but it appears nothing could be further from the truth. Shockingly, up to 62% of the Standard American Diet (and probably the standard South African diet!) is made up of PUFAs so we need to look at this.

We already know, as low-carbers, that saturated fatty acids (SFAs) from animal fats and coconut oil are not harmful – so where do monounsaturated fatty acids (MUFAs) and PUFAs fit in?

Chemically MUFAs and PUFAs are very similar but there’s a slight difference in the structure of their molecules, which changes what they do.

You will find MUFAs in red meat, whole milk products, olives, avocados, nuts and olive oil, which boasts around 75% MUFAs. Olive oil is an excellent source, with naturally occurring vitamin E, which has a positive effect on both heart health and beneficial high-density lipoproteins (HDL), while lowering excessive low-density lipoproteins (LDL). The omega-9 fatty acids present in MUFAs are not ‘essential fats’ – the body is able to make them if needed but, of course, MUFArich types of food are also rich in other nutrients. Olive oil and macadamia oil (which has a similar profile to olive oil) are the only MUFA oils I would include in a healthy diet.