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Nutritional ketosis is a very powerful tool, and it can be used to achieve metabolic health and well-being in people who have diseases associated with insulin resistance or inflammation. There are many myths and misunderstandings about ketogenic diets and nutritional ketosis, and this discussion focuses on the scientific evidence around the safety and efficacy of this approach to nutrition. It can be hard for people to commit to this kind of endeavor when people around them say it is dangerous and that they shouldn't be doing it, so it is important to be confident that if you undertake this, you are doing it in a safe and efficacious way.
In study after study, not just the speaker's own but others as well, a well-formulated ketogenic diet, compared to a standard calorie-restricted low-fat diet, has a greater effect on weight loss, particularly loss of abdominal adipose tissue. The fat mass within the abdomen is the most dangerous fat we carry in our body. For instance, in a study conducted with Dr. Jeff Volek and Dr. Cassandra Forsythe, one of his graduate students, researchers compared a high-carbohydrate, low-fat, calorie-restricted diet to a ketogenic diet. Participants on the ketogenic diet were instructed to eat to satiety, meaning they did not count calories or restrict calories but ate enough to feel they had had enough food and were not hungry. The study ran for 12 weeks. At the end of 12 weeks, weight loss in the high-carbohydrate, low-fat group was about half the weight loss in the ketogenic diet group.
Some critics say that much of the weight loss on a ketogenic diet is water. However, careful measurements of body fat were taken, and the water loss on the ketogenic diet accounted for only about one-fifth of the difference. The high-carbohydrate, low-fat diet group lost five kilograms and the ketogenic diet group lost 10 kilograms, and only about one-fifth of that difference was water; the rest was body fat. More importantly, the researchers used the dual x-ray absorptiometry, or DEXA, technique to measure body fat content. There was a significantly greater reduction in abdominal fat, not just total fat or fat under the skin. Some of the most dangerous fat is mobilized more rapidly when someone gets the ketogenic diet right.
The next most common effect is seen in people who have slightly or markedly elevated blood glucose levels, whether prediabetes or diabetes. A prompt response to the ketogenic diet is a reduction in blood glucose. This makes sense, because eating less carbohydrate means less glucose is produced by digestion, so the level of sugar entering the blood is reduced, which is what is commonly observed. In Dr. Forsythe's study, participants had prediabetes, with blood sugars still slightly elevated. There was a marked reduction in blood glucose in people on the ketogenic diet and no change in blood glucose in people on the high-carbohydrate, low-fat diet.
More interestingly, blood insulin levels were also measured. Insulin is a hormone that moves glucose into cells, so if blood sugar came down, one might expect the body to produce more insulin to move it into cells. Instead, the opposite occurred: insulin levels came down dramatically along with blood glucose. The only way to make sense of this is that the ketogenic diet improved insulin sensitivity, meaning the body's response to any one molecule of insulin is markedly greater. This is a consistent finding across multiple studies and is the basis for the concept that the root cause of Type 2 diabetes can actually be reversed.
Another effect of a well-formulated ketogenic diet is a change in the blood lipid values characteristic of metabolic syndrome, also referred to as prediabetes. Typically, metabolic syndrome involves reduced good cholesterol (HDL), increased triglycerides, and a greater proportion of small, dense, or "bad" LDL cholesterol. In this cohort, triglycerides plummeted. They went down in both groups, but more than twice as much in the patients on the ketogenic diet, even though those patients were eating more fat. HDL went up about 13 percent, which is greater than any HDL response from any available prescription drug. This is a fairly unique benefit of a well-formulated ketogenic diet. The small, dense LDL, which is the most dangerous type, did not go down. If anything, it went down slightly in the high-carbohydrate, low-fat group and dropped sharply in the ketogenic group. All lipid changes moved in the right direction in favor of the ketogenic diet. So concerns about eating a high-fat diet, including eggs, meat, and dairy that contain cholesterol, are not borne out: when the diet is done right, blood cholesterol and blood lipids change in a beneficial way.
On a low-carbohydrate, moderate-protein diet, the majority of dietary calories come from fat, and many of those fats typically come from animal products, dairy, and cocoa butter, which are saturated fats. The question is whether eating a lot of saturated fat is dangerous on a ketogenic diet. People propose that it is dangerous because higher blood levels of saturated fat are associated with greater risk of diabetes, heart attack, and overall mortality. If eating saturated fat raised blood levels, that would suggest danger. However, no one had actually examined what happens to blood levels of saturated fat on a ketogenic diet, so this was studied. Even though people on the high-fat ketogenic diet were eating three times as many grams of saturated fat per day, their blood levels of saturated fat were actually lower than those of the group on the lower-saturated-fat, high-carbohydrate diet. This appears to disconnect intake from blood levels and violates the common saying that you are what you eat. In reality, you are what you save from what you eat. The ketogenic diet teaches the body to burn fat more effectively.
To measure how effectively, a study looked at highly trained athletes, half of whom followed a traditional high-carbohydrate loading regimen and half of whom followed a well-formulated ketogenic diet. These people had followed their diets for at least six months or longer, so those on the ketogenic diet were fully keto-adapted. The resting rate of fat oxidation was about double on the low-carbohydrate ketogenic diet compared to the high-carbohydrate diet. Even though highly trained athletes are theoretically conditioned to burn fat for fuel during exercise, the diet difference doubled their bodies' ability to burn fat at rest. As the researchers had the athletes perform greater and greater levels of exercise, those on the ketogenic diet showed a remarkable ability to use fat for fuel. Athletes like this because they can run on body fat stores much better than when trying to eat and load with carbohydrate. This means that when someone is keto-adapted, the body has the capability of getting rid of saturated fat, so the amount eaten is less important than how much the body saves from what is eaten. Clearly, the body does not store saturated fat when keto-adapted, which suggests saturated fats are not harmful when consumed by someone who is keto-adapted.
Another important area of current research is inflammation. Biomarkers of inflammation, some measured over the last century such as white blood cell count and some more recent additions, predict the later onset of diseases including heart disease, Type 2 diabetes, Alzheimer's disease, and many common forms of cancer. In the study with Dr. Volek and Dr. Forsythe, the researchers measured every biomarker they could think of and came up with 14 different biomarkers of inflammation. When comparing people on the high-carbohydrate diet with people adapted to the low-carbohydrate, high-fat diet, none of the inflammation levels went down more in the high-carbohydrate, low-fat group. In contrast, seven of those 14 were significantly reduced in people on the well-formulated ketogenic diet. On average, there was a marked reduction in inflammation with the ketogenic diet, indicating a wide-ranging anti-inflammatory effect. Until recently, scientists regarded this as a phenomenon: it was observed, but the reason was unknown. It turns out there is a particular gene, something like a traffic cop gene, that regulates the flow of traffic around inflammation. This gene is targeted directly by a primary ketone circulating in the blood, called beta-hydroxybutyrate, or BHB. Ketones talk to your genes, and the genes turn down the heat, through a regulated series of events, to reduce inflammation throughout the body. This likely has very positive effects not only on reducing insulin resistance but also on other common chronic diseases. The inflammation goes down, and scientists now know why and why it is so effective, even at modest ketone levels, the levels achieved just by restricting carbohydrates to less than 5 percent of total calories and keeping protein moderate.
A study with Indiana University Health recruited over 260 people with Type 2 diabetes and put them on a well-formulated ketogenic diet. The study will run for two years, but early data from the first 10 weeks were presented. All participants had a diagnosis of Type 2 diabetes; some were poorly controlled, some fairly well controlled, and some very tightly controlled. The biomarker of diabetes control, hemoglobin A1c or HbA1c, was used to divide participants into high, intermediate, and well-controlled levels. In all three groups, after 10 weeks, hemoglobin A1c decreased, and the effect was greatest in people with the highest levels. Those with the poorest control of their diabetes got the greatest effect, but all three groups benefited. As a result, over half of these people moved from hemoglobin A1c levels in the diabetes range into the non-diabetes range. Normally in diabetes care, better glucose control comes from giving people more drugs. In this study, most medications were removed from five of the seven classes of diabetes medications. The two most dangerous classes, insulin and sulfonylureas, which are most likely to cause hypoglycemia, the most threatening short-term side effect in diabetes management, were either stopped or markedly reduced for the majority of patients. Again there is a paradox: less medication, better control. Better control with less medication is possible because beta-hydroxybutyrate and ketones in general speak to the genes and fundamentally change how the body functions, including how it responds to insulin, so the body gets much greater benefit from far less insulin.
Participants were told to eat to satiety, with limited carbohydrates, moderate protein, and as much fat as they needed. They could put butter on their meat, and butter or dressing on vegetables or use them for dipping. Even so, 75 percent of these patients lost more than 5 percent of their body weight, with an average weight loss of a little over 7 percent in the first 10 weeks. At six months, weight loss in this cohort increased from 7 percent to 12 percent. This is not a short-term quick loss followed by regain but appears to be a sustained, long-term effect. People six months into the study are doing the same thing they were told to do at the start: limit carbohydrates, keep protein moderate, and eat fat to satiety. This gives the body permission to burn a lot of body fat stores because it has become very efficient at burning fat for fuel.
Other conditions have also shown improvement with the ketogenic diet, including general muscle and joint aches and pains. Irritable bowel syndrome typically gets better. Polycystic ovary syndrome in women improves, and people with migraine headaches report reduced frequency or intensity, and some achieve complete remission of migraines when the ketogenic diet is done right. As shown in Dr. Forsythe's study, metabolic syndrome or prediabetes improves, and liver fat levels go down, which is a side effect of poorly controlled diabetes. Improvements in fluid retention and blood pressure are also seen.
This is a very powerful tool with beneficial effects on a number of chronic conditions. However, when a person is taking medicines for these conditions, those beneficial effects usually require a sharp and rapid reduction in medication, which can be dangerous unless a physician who understands this type of diet and how to manage medications is involved. This cannot be done casually: one cannot start the diet and return to the physician six weeks later to ask what to do about diabetes medication, because most of the changes typically occur in the first six days when the diet is done right. The difficulty is finding a doctor who understands this approach, though physician interest is increasing, and with careful searching, one can probably find someone who can help if that assistance is needed.
In conclusion, a well-formulated ketogenic diet is not only safe but can be very effective in reversing disease, and these effects are powerful. However, it must be started with careful monitoring. Stated directly, one must find a physician who can help manage medications properly so the benefits far outweigh any potential risks involving changes in medication use.