In the study, researchers fed mice (!) a keto diet for three days (!), and then ran a glucose tolerance test. They noticed that while the mice on a keto diet had a lower fasting blood glucose, it got higher after the glucose tolerance test and there were signs of a reduced effect of insulin compared to mice on regular mouse chow. That’s basically it.
But people who started following the keto diet noticed weight loss for a few reasons: When you eat carbs, your body retains fluid in order to store carbs for energy (you know, in case it needs it). But when you’re not having much in the carb department, you lose this water weight, says Warren. Also, it's easy to go overboard on carbohydrates—but if you're loading up on fat, it may help curb cravings since it keeps you satisfied.
A small, randomized crossover study published in the Journal of Diabetes Sciences and Technology found that after three months, people who followed a modified, low-carb paleo diet saw greater reductions in their A1C, their triglycerides, their diastolic blood pressure, and their weight than those who followed a traditional diabetes diet. (The approach also increased their levels of LDL, or "good” cholesterol.) The diabetes diet in the study involved consuming no more than 6 g of salt per day, reducing saturated fat and total fat intake, and upping intake of veggies, fiber, whole grains, fruits, and veggies. Compared with the diabetes diet, the paleo diet involved eating less dairy, beans, potatoes, and cereals, and more veggies, fruit, meat, and eggs.
Sleep enough – for most people at least seven hours per night on average – and keep stress under control. Sleep deprivation and stress hormones raise blood sugar levels, slowing ketosis and weight loss a bit. Plus they might make it harder to stick to a keto diet, and resist temptations. So while handling sleep and stress will not get you into ketosis on it’s own, it’s still worth thinking about.