In the context of a well-formulated ketogenic diet (high fat, low carb, moderate protein), the intake of fat is not only safe, but imperative for long-term success. There have been multiple studies of low carbohydrate and ketogenic diets lasting up to three years, with no increase in cardiac events or mortality (Halton, 2006). Furthermore, cardiac risk factors improve, with lowering of triglycerides, improved blood pressure, improved glycemic control, and increased HDL (Dashti, 2004; Hu, 2014; Nordmann, 2006; Feinman, 2015; Mirza, 2009). Interestingly, the largest trial ever done on low fat diets, the Women’s Health Initiative, showed no decrease in heart disease events or mortality (Howard, 2006). Controlled studies have consistently failed to show a clinical association between high saturated fat intake and adverse cardiovascular outcomes (Siri-Tarino, 2010).
The science on cholesterol and saturated fat has evolved greatly in the past few decades. It is now accepted that dietary cholesterol does not raise blood cholesterol, and this has even been recognized in the new dietary guidelines. Multiple large meta-analyses have shown no association between saturated fat intake and cardiovascular events or increased mortality. Both prior studies and our research have shown that paradoxically, in the setting of a ketogenic diet, higher dietary intake of saturated fat actually decreases serum saturated fat (Forsythe, 2008). This is hypothesized to be due to preferential use of dietary saturated fat as fuel in the keto-adapted state.
You can read more on saturated fat here: The Sad Saga of Saturated Fat
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