Moreover, the ketogenic diet also reliably raise the “good” HDL-cholesterol, while also improving most other cardiovascular markers, including blood pressure, as this study shows.24 Thus, the overall effect on cholesterol and other markers for heart disease is positive. In some lean hyper-responders, a keto diet will increase LDL particle number, and this effect needs further investigation.
The backbone of a keto plan is its extraordinarily high fat content, making up 65 to 80 percent of calories daily. Protein—which can raise blood glucose, though not as much as carbohydrate does—makes up 15 to 25 percent of calories on the keto diet. And carbs are even more heavily restricted to just 5 to 15 percent of calories. That’s only about 20 to 50 grams a day (compared with the average 245 grams daily), or the amount in a small apple or a cup of cooked brown rice, respectively.
But even if you’re not trying to lose weight, the keto meal plans might appeal to you. By limiting sugars and processed grains, you lower your risk of type 2 diabetes. Eating an array of heart-healthy fats, like nuts, olive oil and fish, can decrease your risk of heart disease. And while some people stick to a super strict keto diet, with 75 percent of their diet coming from fat, 20 percent from protein and just five from carbs, even a less intense, modified version can help you reap the keto diet’s benefits.
Even in endurance sports that don’t require sprinting, ketogenic-style diets are disadvantageous according to a ketogenic diet and exercise article published in Sports Medicine[5]: “a high-fat, low-carbohydrate ketogenic diet may impair exercise performance via reducing the capacity to utilize carbohydrates, which forms a key fuel source for skeletal muscle during intense endurance-type exercise.” The article concluded, “At present there are no data available to suggest that ingestion of ketone bodies during exercise improves athletes’ performance under conditions where evidence-based nutritional strategies are applied appropriately.”
Achieving ketosis is a pretty straightforward, but it can seem complicated and confusing with all of the information out there.4If you want to learn more about ketosis and the scientific process around it, you can visit a very in-depth discussion about on Dr. Peter Attia’s website. Here’s the bottom line on what you need to do, ordered in levels of importance:
Increases in cholesterol levels need discussion too. We do see temporary increases in cholesterol levels often as individuals transition onto a ketogenic diet. However, when you examine lipid particle size (a more important way to look at the cardiovascular risks), the risk pattern doesn’t seem to increase with a ketogenic diet. Harvard Health has written about lipid particle size here before: http://www.health.harvard.edu/womens-health/should-you-seek-advanced-cholesterol-testing-
Moreover, the ketogenic diet also reliably raise the “good” HDL-cholesterol, while also improving most other cardiovascular markers, including blood pressure, as this study shows.24 Thus, the overall effect on cholesterol and other markers for heart disease is positive. In some lean hyper-responders, a keto diet will increase LDL particle number, and this effect needs further investigation.
The ketogenic diet is a high-fat, adequate-protein, low-carbohydrate diet that in medicine is used primarily to treat difficult-to-control (refractory) epilepsy in children. The diet forces the body to burn fats rather than carbohydrates. Normally, the carbohydrates contained in food are converted into glucose, which is then transported around the body and is particularly important in fueling brain function. However, if little carbohydrate remains in the diet, the liver converts fat into fatty acids and ketone bodies. The ketone bodies pass into the brain and replace glucose as an energy source. An elevated level of ketone bodies in the blood, a state known as ketosis, leads to a reduction in the frequency of epileptic seizures.[1] Around half of children and young people with epilepsy who have tried some form of this diet saw the number of seizures drop by at least half, and the effect persists even after discontinuing the diet.[2] Some evidence indicates that adults with epilepsy may benefit from the diet, and that a less strict regimen, such as a modified Atkins diet, is similarly effective.[1] Potential side effects may include constipation, high cholesterol, growth slowing, acidosis, and kidney stones.[3]

The ketogenic diet is a high-fat, adequate-protein, low-carbohydrate diet that in medicine is used primarily to treat difficult-to-control (refractory) epilepsy in children. The diet forces the body to burn fats rather than carbohydrates. Normally, the carbohydrates contained in food are converted into glucose, which is then transported around the body and is particularly important in fueling brain function. However, if little carbohydrate remains in the diet, the liver converts fat into fatty acids and ketone bodies. The ketone bodies pass into the brain and replace glucose as an energy source. An elevated level of ketone bodies in the blood, a state known as ketosis, leads to a reduction in the frequency of epileptic seizures.[1] Around half of children and young people with epilepsy who have tried some form of this diet saw the number of seizures drop by at least half, and the effect persists even after discontinuing the diet.[2] Some evidence indicates that adults with epilepsy may benefit from the diet, and that a less strict regimen, such as a modified Atkins diet, is similarly effective.[1] Potential side effects may include constipation, high cholesterol, growth slowing, acidosis, and kidney stones.[3]
Note the emphasis on ketosis as a temporary adaptive state. Our ancestors could not be in fasting-induced ketosis permanently because they would eventually exhaust their fat reserves (which were presumably far more limited than ours, owing to the simple fact that they ate less and moved more than we do). They would then progress from fasting to starving, and subsequently die.
Type 2 diabetes. One study found that being on the keto diet for one year reversed diabetes for up to 60 percent of participants. With an average weight loss of 30 pounds, they dramatically reduced or eliminated their need for insulin and no longer needed oral hypoglycemic drugs. The keto diet is also easier to sustain than the calorie-restricted diet or the protein-sparing modified fast.
Variations on the Johns Hopkins protocol are common. The initiation can be performed using outpatient clinics rather than requiring a stay in hospital. Often, no initial fast is used (fasting increases the risk of acidosis, hypoglycaemia, and weight loss). Rather than increasing meal sizes over the three-day initiation, some institutions maintain meal size, but alter the ketogenic ratio from 2:1 to 4:1.[9]
My principal hope in this article is to provide journalists with a resource to do what basic journalism demands, namely to ensure that stories are scientifically balanced and accurate. At the end of this post I provide contacts for some of the credentialed experts who helped me compile this research. Reporters, please seek out these or other low-carb diet experts so you can provide accurate, up-to-date information for your readers.
“However, saturated fat has long been lauded as a heart-harming macronutrient; the American Heart Association recommends no more than 13 grams of saturated fat per day. In fact, Nieca Goldberg, M.D., medical director of the Joan H. Tisch Center For Women’s Health at NYU Langone Medical Center, said saturated fats can increase bad cholesterol.” -Christina Stiehl, PopSugar reporter17

On your keto food list, stick to low-glycemic sweeteners to avoid spikes in blood sugar, and avoid fillers and binders such as maltodextrin and dextrose, which can spike blood sugar and contain sneaky carbs. Sugar alcohols such as maltitol or xylitol may read as no sugar on a label, but be aware that they will still cause moderate glycemic response when digested.

A survey of 1,580 low-carb consumers published in late 2017 by the Journal of Insulin Resistance45 found that while more than 11% of respondents reported using sleep-aids before beginning their low-carb diet, less than 5% reported using them after their diet. Moreover, nearly seven in 10 reported improved quality of sleep after dieting while only 3.4% said their sleep quality had worsened.


As in adults, glucose is the predominant cerebral fuel for the fetus and newborn. Studies in experimental animals and humans indicate that cerebral glucose utilization initially is low and increases with maturation with increasing regional heterogeneity. The increases in cerebral glucose utilization with advancing age occur as a consequence of increasing functional activity and cerebral energy demands… glucose plays a critical role in the developing brain, not only as the primary substrate for energy production but also to allow for normal biosynthetic processes to proceed.
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It seems like everyone is talking about the keto diet — the high-fat, low-carb eating plan that promises to turn your body into a fat-burning machine. For that reason, keto has surged in popularity over the past year as a lose-weight-fast strategy. Thank Hollywood A-listers and professional athletes like Halle Berry, Adriana Lima, and Tim Tebow who’ve publicly touted the diet’s benefits, from shedding weight to slowing down aging. Here’s everything you need to know about going keto.
There are three instances where there’s research to back up a ketogenic diet, including to help control type 2 diabetes, as part of epilepsy treatment, or for weight loss, says Mattinson. “In terms of diabetes, there is some promising research showing that the ketogenic diet may improve glycemic control. It may cause a reduction in A1C — a key test for diabetes that measures a person’s average blood sugar control over two to three months — something that may help you reduce medication use,” she says.
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