What is a Ketogenic Diet?
A ketogenic diet, often referred to as the "keto diet," is a high-fat, low-carbohydrate eating plan designed to induce a metabolic state called ketosis. Here are the key aspects of a ketogenic diet:
Macronutrient Breakdown
The typical macronutrient distribution in a ketogenic diet is:
70-80% of calories from fat
10-20% of calories from protein
5-10% of calories from carbohydrates
This usually translates to consuming less than 50 grams of carbohydrates per day, though some versions may allow up to 50 grams[1][3].
How It Works
By drastically reducing carbohydrate intake and replacing it with fat, the body is forced to enter a metabolic state called ketosis. In this state, the body becomes efficient at burning fat for energy. The liver converts fat into ketones, which can supply energy for the brain[1][4].
Foods Allowed
A ketogenic diet typically includes:
High-fat meats
Fatty fish
Oils and butter (NO POLYUNSATURATED FATS - corn, soybean, canola oils)
Nuts and seeds
High-fat dairy like cheese
Low-carb vegetables (e.g., leafy greens)
Avocados
Foods to Avoid
The diet restricts or eliminates:
Grains and starches
Most fruits
Legumes and beans
Root vegetables
Sugar and most processed foods
Most dairy products (except high-fat options)[3][5]
Potential Benefits
Weight loss
Improved blood sugar control
Potential reduction in heart disease risk factors
Possible benefits for certain neurological conditions[4][5]
Adjunctive therapy for Cancer
Considerations and Risks
While the ketogenic diet can be effective for weight loss and certain medical conditions, it's important to note:
It can be difficult to follow long-term
It may lead to nutrient deficiencies if not well-planned
Some people experience short-term side effects known as the "keto flu"
It's crucial to consult with a healthcare professional before starting a ketogenic diet, especially if you have any pre-existing health conditions.
Citations:
[1] https://www.healthline.com/nutrition/ketogenic-diet-101
[2] https://www.eatright.org/health/wellness/diet-trends/what-is-the-ketogenic-diet
[3] https://www.bbcgoodfood.com/health/special-diets/what-ketogenic-diet
[4] https://nutritionsource.hsph.harvard.edu/healthy-weight/diet-reviews/ketogenic-diet/
[5] https://www.ncbi.nlm.nih.gov/books/NBK499830/
[6] https://www.nm.org/healthbeat/healthy-tips/nutrition/pros-and-cons-of-ketogenic-diet
[7] https://foodinsight.org/keto-diet-101-what-to-know-before-you-commit/
Ketone Levels
The optimal range of ketones for nutritional ketosis on a ketogenic diet is generally considered to be between 0.5 to 3.0 mmol/L (or mg/dL) of beta-hydroxybutyrate (BHB) in the blood. Here are the key points:
1. Nutritional ketosis typically begins at around 0.5 mmol/L of blood ketones[1][3].
2. The "optimal ketosis" range is often cited as 1.5 to 3.0 mmol/L[1][4].
3. For weight loss purposes, the "sweet spot" is considered to be 1.5 to 3.0 mmol/L[5].
4. Ketone levels above 3.0 mmol/L and up to about 7 or 8 mmol/L are still physiological but enter the realm of therapeutic ketosis, which may be used for managing certain medical conditions[3].
5. It's important to note that ketone levels may decrease over time as the body becomes more efficient at using ketones, even while maintaining a ketogenic diet[4].
6. Some researchers and clinicians consider the range of 0.5 to 1.5 mmol/L as "light nutritional ketosis," which can still be beneficial[5].
7. For most people following a ketogenic diet for general health or weight loss, staying within the 0.5 to 3.0 mmol/L range is considered appropriate[3][6].
8. Ketone levels can vary throughout the day and may be influenced by factors such as diet, exercise, and individual metabolism[5].
It's crucial to remember that while measuring ketones can be helpful, it's not the only indicator of success on a ketogenic diet. Factors such as overall health improvements, energy levels, and individual goals should also be considered. Additionally, people with certain medical conditions, especially type 1 diabetes, should consult with a healthcare provider before attempting a ketogenic diet or interpreting ketone levels[7][8].
Citations:
[1] https://keto-mojo.com/article/testing-what-should-ketone-levels-be/
[2] https://greatist.com/eat/ideal-ketosis-level-for-weight-loss
[3] https://www.carbmanager.com/article/yrdolbiaacmapeqp/what-should-your-ketone-levels-be
[4] https://optimisingnutrition.com/nutritional-ketosis/
[5] https://www.diabetes.co.uk/keto/measuring-ketosis-on-a-keto-diet.html
[6] https://www.virtahealth.com/faq/how-do-i-get-into-nutritional-ketosis
[7] https://www.medicinenet.com/do_ketones_mean_youre_burning_fat/article.htm
[8] https://www.nutrisense.io/blog/what-is-a-good-ketone-level-for-ketosis
But aren’t saturated fats bad for me??? Aren’t polyunsaturated fats like corn, soybean, canola and sunflower oils good for me???
The theory that saturated fats are bad for you came from “the diet heart hypothesis” promulgated by Ansel Keyes based on his epidemiological study known as the “7 Country Study”. It was based on giving people food questionnaires and comparing what they ate to the amount of heart disease they had. However, food questionnaires are notoriously poor as a source of reliable information as most people can’t recall what they ate over a long period of time. But Ansel Keyes also “cherry picked” his data as he actually studied 23 countries and only chose 7 for his study. Ansel Keys had a large influence on the first dietary guidelines proposed by the US government in 1978 which brought us the food pyramid. Since that time the US has become one of the most sick and obese countries in the world. See the research section below for another epidemiological study using 42 countries that contradicts the 6 county study and finds no association or an inverse association of saturated fat to heart disease. One must also consider the corruption involved in making of the uS dietary guidelines. The food industry, particularly Big Sugar, has connections with those who sit on the panel that make the guidelines. The American Heart Association was, and still is, funded heavily by Proctor & Gamble and Big Food. Big Pharma profits off Americans being sick and has no desire for us to be healthy. Big Pharma wants us to be treated and cured with pills, not diet. For more information, see my separate page on this topic.
Research on Saturated Fats
*See my section on fats
Grasgruber P, Sebera M, Hrazdira E, et al. Food consumption and the actual statistics of cardiovascular diseases: an epidemiological comparison of 42 European countries. Food Nutr. Res. 2016;60(0):31694.
Kearns CE, Schmidt LA, Glantz SA. Sugar Industry and Coronary Heart Disease Research: A Historical Analysis of Internal Industry Documents. JAMA Intern. Med. 2016;176(11):1680.
Malhotra A, Redberg RF, Meier P. Saturated fat does not clog the arteries: coronary heart disease is a chronic inflammatory condition, the risk of which can be effectively reduced from healthy lifestyle interventions. Br. J. Sports Med. 2017;51(15):1111.
What are Ketones?
Ketones are energy molecules produced by the liver when the body breaks down fats for fuel instead of carbohydrates. There are three main types of ketone bodies produced during ketosis:
Types of Ketones
1. Beta-hydroxybutyrate (BHB)
BHB is the most abundant ketone body, making up about 78% of total ketones in the blood[1][3].
It's the primary ketone used for energy by the body and brain[1].
BHB is the ketone most commonly measured in blood ketone tests[5].
2. Acetoacetate (AcAc)
Acetoacetate is the first ketone body produced in the liver[3].
It can be converted to beta-hydroxybutyrate or spontaneously break down to acetone[3].
AcAc makes up about 20% of ketones in the blood[1].
3. Acetone
Acetone is produced in smaller amounts, mainly from the spontaneous breakdown of acetoacetate[1][3].
It's the ketone responsible for the characteristic "fruity" breath odor sometimes noticed in deep ketosis[1].
Acetone is the least abundant ketone, comprising only about 2% of ketones in the blood[1].
Ketone Production and Utilization
The liver produces ketones through a process called ketogenesis when glucose availability is low[2]. Beta-hydroxybutyrate and acetoacetate are the two ketones primarily used by the body for energy[2]. Most organs and tissues can use ketone bodies as an alternative energy source, with the brain being a major consumer during periods of low glucose availability[2].
Measuring Ketones
Blood ketone levels can be measured to determine the depth of ketosis:
Nutritional ketosis is typically defined as blood ketone levels between 0.5 - 3.0 millimoles per liter (mmol/L)[5][7].
Levels above 3.0 mmol/L may indicate a risk for ketoacidosis, especially in people with diabetes[7].
It's important to note that while nutritional ketosis is generally considered safe for most people, ketoacidosis is a dangerous condition that requires immediate medical attention[5][7].
Ketosis vs. Ketoacidosis
Ketosis and ketoacidosis are distinct metabolic states:
Ketosis is a normal metabolic process where ketone levels are mildly elevated (0.5 - 3.0 mmol/L) and the body's acid-base balance is maintained[3].
Ketoacidosis is a pathological state with extremely high ketone levels (typically >10 mmol/L) that causes metabolic acidosis and is a medical emergency[3].
Understanding the different types of ketones and their roles can help in monitoring and managing ketosis, whether for weight loss, metabolic health, or managing certain medical conditions under proper medical supervision.
[1] https://perfectketo.com/what-are-ketones/
[2] https://www.ncbi.nlm.nih.gov/books/NBK493179/
[3] https://en.wikipedia.org/wiki/Ketosis?wasRedirected=true
[4] https://my.clevelandclinic.org/health/body/25177-ketones
[5] https://www.healthline.com/nutrition/ideal-ketosis-level-for-weight-loss
[6] https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/ketone-bodies