What you thought you knew about fat and its influence on cholesterol, increased risk of heart disease and weight gain is all a fat fallacy.
Blame it on the power of suggestion and the frenzy of marketing that developed an entire industry of low and fat free foods, but today, even with all the low fat food around, we're getting fatter than ever...
The truth is: it's not Fat that makes us fat and that skinny blueberry muffin from Startbucks is not your friend...
So what are the FA(C)TS....
All foods have an energy value which is expressed in terms of how much fuel it supplies to the body.
This fuel value is expressed in Calories or Kilocalories. Fat is the most energy dense food type (at 9 Cal/g), followed by Alcohol (7Cal/g); Protein & Carbs (both 4Cal/g).
Fats may be the most energy dense, but they are important for our cellular structure, metabolism, nutrient and waste storage and supply the body with fat soluble vitamins (A, D, E and K). Fat also helps to insulate our core organs and regulates body temperature and in the case of cholesterol, plays a vital part in producing hormones such as testosterone, oestrogen, progesterone and cortisone.
If it's not fat that makes us fat, what's to blame?
Remember that Starbucks skinny muffin I mentioned? Well most low or no fat foods rely on other ingredients to give it flavour, and refined sugar is a big culprit. Eating refined sugar causes a rapid rise in blood glucose levels resulting in the body secreting a large dose of insulin. Insulin helps to lower our circulating blood glucose levels by transporting the glucose into the cells, where it is stored as glycogen.
Once our blood glucose levels are lowered, neurotransmitters signal to the brain that cells need more glucose, resulting in you feeling hungry and craving sugar yet again... and so the cycle continues. Sugar high followed by insulin induced low.
Insulin has a fat-storage effect causing cells to preferentially use carbohydrates instead of fatty acids for energy and indirectly stimulates fat accumulation in adipose tissue. So the more insulin we release, the more our bodies end up storing (rather than burning) fat for energy.
The BIG TRUTH is that eating excess fat can contribute to weight gain because fat is an energy dense source of nutrition. However, the primary culprit for excess body fat and many degenerative diseases (such as heart disease, cancer and type 2 diabetes) is about eating too much carbohydrate and sugar and not doing enough to burn off the excess energy before it needs to be stored as fat.
Bowen, R; Colorado University (2009); The physiologic effects of insulin; http://www.vivo.colostate.edu/hbooks/pathphys/endocrine/pancreas/insulin_phys.html
Garrow, J; James, W; Ralph, A; (2000); Human Nutrition and Dietetics, Churchill Livingstone
La Berge, AF, (2008); How the Ideology of Low Fat conquered America, Jour. History of Medicine,
Moir, H; (2014); Musculoskeletal regulation of glucose; Functional Sports Nutrition,