The idea that ketosis is human beings’ natural state is also contradicted by the heavy dependence of human embryonic and fetal development on glucose. All women become insulin resistant during normal pregnancy as glucose is directed toward the developing baby. Pregnant women deprived of carbohydrates are at high risk of developing ketoacidosis in later pregnancy. This dangerous condition can occur as the nutrient needs of the developing fetus reach their peak and drive up maternal ketone production.
These affect your brain and spine, as well as the nerves that link them together. Epilepsy is one, but others may be helped by a ketogenic diet as well, including Alzheimer’s disease, Parkinson’s disease, and sleep disorders. Scientists aren’t sure why, but it may be that the ketones your body makes when it breaks down fat for energy help protect your brain cells from damage.
Ketoacidosis, on the other hand, is dangerous. But it’s usually limited to people with type 1 diabetes, striking when their glucose levels rise due to illness or a missed insulin dose. Without insulin, cells can’t take in glucose, so they burn fat for fuel instead, producing exceptionally high ketone levels—much higher than the amount generated by the keto diet. That, in combination with high blood glucose levels, essentially poisons the blood. “It’s very easy to tell the difference between nutritional ketosis, which has no negative symptoms [aside from ‘keto breath,’ which can smell like nail polish remover], and dietary ketoacidosis, which is an illness that requires hospitalization and causes lethargy, abdominal pain, nausea, vomiting, rapid breathing, and lack of appetite,” says William Yancy, MD, program director at the Duke Diet and Fitness Center in Durham, North Carolina.
When you’ve eaten all of the crustless spinach quiche and keto frittata recipes that you can, these keto everything bagels are another great breakfast staple. With their help, you don’t have to cut out your favorite breakfast sandwiches. You can also try a bread-less keto breakfast sandwich with chicken sausage patties as the “buns” when you’re craving a keto-approved breakfast option.
Another difference between older and newer studies is that the type of patients treated with the ketogenic diet has changed over time. When first developed and used, the ketogenic diet was not a treatment of last resort; in contrast, the children in modern studies have already tried and failed a number of anticonvulsant drugs, so may be assumed to have more difficult-to-treat epilepsy. Early and modern studies also differ because the treatment protocol has changed. In older protocols, the diet was initiated with a prolonged fast, designed to lose 5–10% body weight, and heavily restricted the calorie intake. Concerns over child health and growth led to a relaxation of the diet's restrictions. Fluid restriction was once a feature of the diet, but this led to increased risk of constipation and kidney stones, and is no longer considered beneficial.
Before starting, ask yourself what is really realistic for you, Mattinson suggests. Then get your doctor’s okay. You may also work with a local registered dietitian nutritionist to limit potential nutrient deficiencies and talk about vitamin supplementation, as you won’t be eating whole grains, dairy, or fruit, and will eliminate many veggies. “A diet that eliminates entire food groups is a red flag to me. This isn’t something to take lightly or dive into headfirst with no medical supervision,” she says.
Infants and patients fed via a gastrostomy tube can also be given a ketogenic diet. Parents make up a prescribed powdered formula, such as KetoCal, into a liquid feed. Gastrostomy feeding avoids any issues with palatability, and bottle-fed infants readily accept the ketogenic formula. Some studies have found this liquid feed to be more efficacious and associated with lower total cholesterol than a solid ketogenic diet. KetoCal is a nutritionally complete food containing milk protein and is supplemented with amino acids, fat, carbohydrate, vitamins, minerals and trace elements. It is used to administer the 4:1 ratio classic ketogenic diet in children over one year. The formula is available in both 3:1 and 4:1 ratios, either unflavoured or in an artificially sweetened vanilla flavour and is suitable for tube or oral feeding. Other formula products include KetoVolve and Ketonia. Alternatively, a liquid ketogenic diet may be produced by combining Ross Carbohydrate Free soy formula with Microlipid and Polycose.