A ketogenic diet is comprised of approximately 10% of daily calories coming from healthy carbohydrates such as leafy greens, nonstarchy vegetables, and limited amounts of legumes and berries; 20% of daily calories coming from proteins such as omega-3-rich fish and grass-fed animal protein; and ~70% of daily calories coming from high-quality fats such as avocado, unsaturated and medium-chain triglyceride oils, nuts and seeds, and coconut.
Meanwhile, more than 70 trials have examined the health effects of a low-carb diet. They attest to the benefits64 associated with ketosis and low-carb diets, including a reduction in body weight and body mass index, improved cardiovascular risk factors including blood pressure, and the reversal of Type 2 diabetes. It is virtually impossible to imagine that a diet with so many health improvements in the ‘near term’ (2 years) could ultimately shorten life—and the study authors offer no possible mechanism to explain how this might happen.
Ketosis is an adaptive state that allowed our ancestors to survive temporary food shortages. When food was not available at all, or the only food available was extremely low in energy (such as leaves and grasses), their bodies could start to break down their body fat reserves after a couple of days. Ketone bodies were generated as a result allowing them to sustain their brains and preserve their muscle and other vital proteins.
A ketogenic diet helps control blood sugar levels. It is excellent for managing type 2 diabetes, sometimes even leading to complete reversal of the disease. This has been proven in studies. It makes perfect sense since keto lowers blood-sugar levels, reduces the need of medications and reduces the potentially negative impact of high insulin levels.