Health Concerns

Are exogenous ketones safe?

Exogenous ketone esters have been found to be safe in humans and animals. Additionally, ketone salts have been granted GRAS (generally recognized as safe) status.  Several studies have used both ketone salts and ketone esters in both animals and humans with no adverse side effects.  A recent study in 2020 showed no adverse effects on consuming over 25 grams of ketone salts daily for 90 days in healthy adults.

Are MCT supplements safe?

Yes! No adverse effects were found in people taking 30 grams of MCTs a day (much higher than typically consumed) for thirty days. Additionally, 1 gram of MCT per kilogram of body weight has been established as safe. However, MCTs can have gastrointestinal side effects, such as nausea and diarrhea, so we highly recommend starting slow and building your way up to see how much you can tolerate.

What is the difference between nutritional ketosis and ketoacidosis?

Nutritional ketosis is characterized by a controlled increase in ketones, along with reductions in blood glucose and normal blood pH. Ketoacidosis is characterized by the uncontrolled increase in ketone production (higher than 15 mmol) despite elevated blood glucose levels and results in dangerous decreases in blood pH ; this is mainly a concern for type 1 diabetics. Ketogenic diets and ketone supplementation typically do not raise ketone levels past 5 to 7 mmol.

Is a ketogenic diet safe?

Yes, when properly formulated, the ketogenic diet is safe. If any of the following affect you, a ketogenic diet may not be right for you—talk to your doctor.

Which tissues use ketones?

Ketones can be used by nearly all of the cells and tissues in the body, though not used by the liver (where they are made). Some cells, like those in certain regions of the brain and red blood cells, can use only glucose for energy, but the amount of glucose the body can produce from gluconeogenesis is plenty to provide those cells with what they need when carbohydrate consumption is low.

Can the brain use ketones?

Unlike most fatty acids, ketones can be taken in and used as an energy source for the brain. In fact, the brain may actually prefer ketones to glucose; studies have shown that ketone uptake by the brain increases as blood ketone levels rise . There is also a lot of research demonstrating that a ketogenic diet can have brain-protecting effects in various types of damaged neurons, possibly due to the neurons receiving greater fuel reserves through ketones, less oxidative stress, and less inflammation . Even when glucose uptake by the brain is impaired, as it is in people with Alzheimer’s, traumatic brain injury, and Parkinson’s, ketones can still be utilized.

Can the ketogenic diet help manage certain health challenges?

Absolutely. Obesity and insulin resistance are at the root of several diseases, including type 2 diabetes and heart disease, and the fact that both can be improved on a ketogenic diet may suggest that the diet can help with those situations. Additionally, there is very strong evidence that the ketogenic diet benefits conditions such as epilepsy and GLUT 1 deficiency.  Further research is exploring how the diet may help with conditions like type 2 diabetes, Alzheimer’s, Parkinson’s, ALS, multiple sclerosis, depression, PTSD, and cancer.  However, please consult your primary care doctor and physician before making any changes in your diet for therapeutic purposes.

What is insulin resistance, and how do I know if I have it?

Insulin resistance is the inability to effectively utilize insulin, the hormone that moves glucose from the bloodstream into cells. Insulin resistance means that insulin is not properly communicating with cells, and it can contribute to many metabolic diseases, particularly type 2 diabetes. If you often feel lethargic and easily gain weight from consuming carbohydrates, there is a high probability that you have some degree of insulin resistance. Ask your doctor to test your fasting blood glucose and insulin levels or, if possible, run an oral glucose tolerance test.

To run an at home oral glucose tolerance test:

  1. Do an overnight fast (12 hours).  Upon waking up in the morning measure your fasting baseline blood glucose
  2. Drink 75 grams of a glucose/sugar containing drink (i.e sports drink, orange juice, etc)
  3. Measure your glucose over 120 minutes (0,30,60,90, 120 min)
  4. Record your numbers and see how they compare with your baseline (ideally within 80-120 mg/dL)

My cholesterol has gone up since starting a ketogenic diet. What should I do?

Total cholesterol is not the best marker to look at because it does not take into consideration the composition of the cholesterol. The ketogenic diet has been shown to increase HDL (good) cholesterol, which would lead to an increase in total cholesterol but would be beneficial overall. Be sure to have your doctor check the breakdown of your blood lipid tests and look for better markers, such as VLDL,LDL-to-HDL ratio, triglycerides, and even high sensitivity CRP (not traditionally part of cholesterol panel, but can be measured with an NMR Lipoprofile test).

I’m concerned about raising my triglyceride levels. Will a high-fat diet raise triglycerides?

No! It’s a common myth that eating a lot of fat causes high triglyceride levels. However, research has found that when a high-fat diet is paired with carbohydrate restriction, triglyceride levels actually drop.

My doctor said a ketogenic diet is bad. What should I do?

We still hear this all the time, in spite of all the research showing the benefits of keto. The best thing you can do is to educate yourself and offer educational materials to your doctor. If that doesn’t work, it may be time to consider a new physician. For those looking for a doctor who will support the ketogenic diet, a solid list can be found here.

Also, check out our Doctor PDFs in Keto Club that can be printed and given to your doctors to provide them with easy science.

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