The ketogenic diet tries to bring carbohydrates down to less than 5 percent of a person’s daily caloric intake – which means eliminating most grains, fruit, starchy vegetables, legumes and sweets. Instead, it replaces those calories with fat. That fat is turned into ketone bodies, which are an alternative energy source: besides glucose derived from carbohydrates, ketones from fat are the only fuel the brain can use.
The improvement in glycemic control occurred while medications for diabetes were discontinued or reduced in most participants (Table (Table5).5). During the study, hypertension and hyperlipidemia medication doses were not increased from baseline nor were new agents added, except in 3 individuals. No serious adverse effects related to the diet occurred. One participant had a hypoglycemic episode requiring assistance from emergency services after he skipped a meal but the episode was aborted without need for transportation to the emergency room or hospitalization.
In the study, the researchers fed mice a ketogenic diet for several days and expected to find a favorable outcome — perhaps weight loss or another indication of improved health. Instead, they found that the liver began resisting insulin almost immediately and the mice were unable to regulate their blood sugar levels after only three days on the diet. (Insulin resistance, meaning that cells in the body don't respond to insulin, is a key characteristic of type 2 diabetes.)
Many diet plans cut out entire food groups, which can create nutrient deficiencies as well as health problems. For instance, if the diet is very low in carbohydrates and you have type 1 diabetes or type 2 diabetes, it’s probably not a good fit. And if it’s too restrictive and you’re pregnant or breastfeeding, it’s not a good idea, either. Keep in mind that pregnancy is not a time for weight loss. Speak with your doctor before making any changes to your diet if you are pregnant or breast-feeding.
You'll find lots of free Mediterranean diet resources on the Oldways website, including an easy-to-understand food pyramid; a printable grocery list; gender- and age-specific tips on making the Mediterranean switch; a quick-read "starter" brochure; a recipe newsletter; and even a glossary defining Mediterranean staples, from bruschetta to tapenade.
Choose Liquid Calories Wisely. Sweetened drinks pile on the calories, but don't reduce hunger like solid foods do. Satisfy your thirst with water, sparkling water with citrus, skim or low-fat milk, or small portions of 100% fruit juice. Try a glass of nutritious and low-calorie vegetable juice to hold you over if you get hungry between meals. Be careful of alcohol calories, which add up quickly. If you tend to drink a glass or two of wine or a cocktail on most days, limiting alcohol to the weekends can be a huge calorie saver.