Going Keto - Does eating fat make me fat?
Eating fat makes us fat — this seems like a no-brainer concept, right? After all, among the three macronutrients (carbohydrates, proteins and fats), fats provide the most calories. It supplies 9kcal/g, while carbohydrates and proteins provide 4kcal/g. Then how are low carb, high fat diets like the ketogenic (keto) diet able to help people lose weight? Well, before we find out more about how the keto diet works, let’s first understand why and how dietary fat can lead to body fat.
Unlike carbohydrates and proteins, fats stimulate excess energy intake due to its high palatability and lack of satiating power. When one is regularly exposed to high fat meals, especially when hungry, it can result in overconsumption of calories, with obesity as a potential end result.
Overfeeding studies indicate that metabolic adaptations to changes in dietary fat amount are slow, compared to adaptations to changes in dietary carbohydrate, which are nearly immediate. One’s ability to decrease food intake due to food eaten earlier is also impaired when ensuing food items are high fat and particularly so, when they are both high fat and high sugar.
However, when studies were regulated to be normal calorie intakes, it has been shown that low fat, high carbohydrates diets actually slowed down metabolism and contributed to the storage of belly fat. On the other hand, those who followed high fat diets (such as the Keto diet) experienced a faster metabolism, while eating the same amount of calories. Another controlled feeding study, which also compared high fat and low carb diets with high carb and low fat diets, showed similar results.
Lastly, a crossover trial (same group of participants being used to test different conditions), was conducted to see the metabolic effects of different diets on a fixed group of individuals. Despite both diets providing a fixed amount of calories, the high fat group ended up burning an average of 300 more calories a day than the low fat group. The high fat group also showed an improvement in lower LDL (bad) cholesterol.
In yet another study, a low carbohydrate, high fat diet, led to a decrease in BMI, body weight, body fat percentage, and waist to hip ratio compared to high carbohydrate diets.
The type of fat you eat makes a difference
But before we start celebrating, here’s something important to note about why these controlled, high fat keto diet studies work. It depends on the type of fats being eaten. Healthy fats like avocados, olive oil, nuts and seeds, and eggs will no doubt be better than unhealthy fats like pork belly, streaky bacon and deep fried snacks. A keto diet isn’t just high in fats, it largely comprises of heart healthy unsaturated fats.
Moderation is key
So does eating fat make us fat? Yes. Overconsumption of any macronutrient can cause weight gain. The best way is always to practise moderation. Fats are an essential macronutrient which helps our body function well. However, fats such as saturated and trans fats can raise LDL cholesterol level, putting one at higher risk of heart disease. Therefore, instead of not consuming fat entirely, seek to include unsaturated fats in our diet whenever possible.
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