While reducing intake of saturated fats is a widely known recommendation for preventing cardiovascular-related issues, the replacement of saturated fats with carbohydrates (particularly when refined) does not benefit prevention. In fact, this replacement with carbohydrates has actually been shown to increase coronary heart disease risk.
What does benefit prevention of these cardiovascular problems? Replacing saturated fat* or carbohydrate with healthy unsaturated fats, such as polyunsaturated fats and monounsaturated fats.
*There has been a lot of debate about the effects of saturated fat – view this source for more info
Studies have shown each 5% increase in daily caloric intake from polyunsaturated fatty acids (PUFA) correspond to a 10% decrease in coronary heart disease risk.
Omega-3 vs omega-6 PUFA:
The ratio of intake of omega-3 to omega-6 should always be fairly low as having too much omega-6 puts you at risk of high blood pressure and inflammation.
Omega-6 is found in vegetable oils, fast foods, dairy, and meats. Due to today’s modern diet, many people consume too much omega-6. While small amounts of omega-6 are good for heart health, having too much puts you at risk of high blood pressure and inflammation.
Omega-3 can be found in fatty fish (salmon, tuna, sardines), flaxseeds, walnuts, chia seeds and olive oil. These play an important role in reducing inflammation and supporting skin/hair health. Unlike omega-6, it is believed that people do not consume enough omega-3.
The importance of consuming monounsaturated fat (MUFA) has been investigated within the context of the Mediterranean diet. In this diet, around 22-27% of daily caloric intake is from MUFA, whereas less than 10% come from PUFA, with limited exposure to trans-fats. This provides a high amount of vitamin E and also supports heart health, mental health (i.e. Alzheimers), and protects against type 2 diabetes.
Everything in moderation!
It is important to note that while omega-3 have been shown to protect against cancer, arthritis, and other conditions, too much of any nutrient does not offer more protection. Just because something is healthy in small amounts does not automatically make it healthier in larger amounts, in fact this can be harmful. At the end of the day, fats are still calorie-dense and consuming more than the recommended 20-35% daily calories can cause weight gain. A healthy balance in one’s diet is the best proven way to get all of the nutrients your body needs.
To read more about the healthy approach to dietary fats, this research article has a lot of helpful information: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5577766/