As always, Paleo Mom brings claims about saturated fat back to earth. Even though the link between saturated fat and heart disease is mostly bunk (though not for everyone), going overboard on saturated fat carries other health risks. Moderation is best.
While eating excessive amounts of saturated fat doesn’t seem to be a good idea, eating too little saturated fat could also be a problem. Why? Well, when we cut way back on saturated fat, we have to either replace those calories with other forms of fat (monounsaturated and polyunsaturated (PUFA)), or we have to eat a diet low in total fat (and fill in the rest with carbohydrates and protein).
Although monounsaturated fats are pretty neutral, we run into problems when increasing our PUFA intake (especially in the form of omega-6 fatty acids). Polyunsaturated fats have very delicate, fragile structures that are prone to oxidizing. Although they do play an important role in health when eaten in proper quantities, excessive amounts can be harmful: the PUFAs we eat become incorporated into our cell membranes and can increase our risk of free radical damage (leading to a cascade of problems such as higher cancer risk and higher risk of heart disease!). Omega-6 PUFAs in particular tend to be pro-inflammatory, especially if they’re not adequately balanced by omega-3s. So, if we try to avoid saturated fat and simply replace it with PUFAs, we’re creating a macronutrient profile with a new set of problems!
The other option, eating a diet low in total fat, isn’t a great strategy either. While there are definitely some vocal proponents of low-fat diets out there (such as Dean Ornish), the bulk of the available evidence points to low-fat diets having plenty of risks! For one, we need some dietary fat to optimize the absorption of the fat-soluble vitamins A, D, E, and K (which are critical to tons of processes in our bodies). Also, low-fat diets and having low levels of serum cholesterol (which tend to go hand-in-hand) have been linked to a variety of health conditions, including depression and suicide (low-fat diets may impair serotonin receptors by decreasing the fats in nerve-cell membranes), anxiety, aggression, other violent behavior, premature death, and even cancer (fat and cholesterol are important for the integrity of cell membranes).
Overall, the research points towards a moderate fat intake (30-40% of calories, perhaps as high as 50% for some people) and moderate saturated fat intake (10-20% of calories) being ideal for maintaining all aspects of our health.