The use of exogenous ketones has garnered significant attention in recent years, both in athletic performance and overall health. These supplements offer a way to elevate blood ketone levels without strict dietary restrictions. This article explores the potential benefits of exogenous ketones, particularly in the context of weight loss, while considering the existing scientific evidence.
Understanding Ketosis and Ketones
To understand the role of exogenous ketones, it’s crucial to grasp the concept of ketosis. In a typical high-carbohydrate diet, the body relies on glucose derived from carbohydrates for fuel. However, when carbohydrate intake is drastically reduced (less than 50 grams per day), the body seeks alternative fuel sources, primarily fat. This metabolic shift leads to the production of ketone bodies, such as acetoacetate and beta-hydroxybutyrate (β-OHB), which replace glucose as the primary energy source. This state is known as ketosis.
Ketosis can also be achieved through prolonged fasting or strenuous exercise. The ketone bodies produced during ketosis can provide energy to the brain, heart, and muscles. Some researchers believe that ketones themselves contribute to the weight loss associated with ketogenic diets.
Exogenous Ketones: A Shortcut to Ketosis?
Exogenous ketones are synthetically produced ketones consumed through supplements. These supplements aim to mimic the effects of endogenous ketones, which are naturally produced by the body.
There are two main types of exogenous ketone supplements:
Read also: Are Perfect Keto Ketones Worth Buying?
- Ketone Salts: These consist of ketones bound to minerals like sodium, potassium, calcium, or magnesium. They are typically available in powder form and mixed with liquids.
- Ketone Esters: These are ketones linked to another compound called an ester and are usually packaged in liquid form. Ketone esters are primarily used in research settings and are less readily available for purchase.
Both ketone salts and ketone esters have been shown to elevate blood ketone levels, simulating the state of ketosis achieved through a ketogenic diet. For instance, one study showed that supplementing with approximately 12 grams of ketone salts increased blood ketone levels by over 300%. This elevation in blood ketone levels can be beneficial for individuals seeking to transition into ketosis without adhering strictly to a ketogenic diet.
Potential Weight Loss Benefits of Exogenous Ketones
Ketone supplements are thought to have many of the same health benefits as a ketogenic diet, including weight loss. People also take ketone supplements along with a ketogenic diet, especially when first beginning the diet. This reduces the time it takes to reach ketosis and lessens the unpleasant effects that may come from transitioning from a standard, higher-carb diet to a ketogenic one.
Appetite Suppression
One potential benefit of exogenous ketones for weight loss lies in their ability to suppress appetite. A 2017 study published in Obesity found that ketone supplement consumption may be useful for suppressing appetite. Participants who consumed a ketone supplement after an overnight fast reported lower hunger and desire to eat, along with reduced concentrations of the hunger hormone ghrelin. These findings have been replicated in other studies.
However, it's important to note that the appetite-suppressive effects of exogenous ketones may be more pronounced when taken in a fasted state. Studies have shown that blood ketone levels are higher in those who haven't eaten before taking a ketone supplement compared to those who have. This suggests that exogenous ketones may be most effective for appetite control when taken on an empty stomach, such as in the morning.
Impact on Energy Balance and Recovery
Interestingly, some research suggests that exogenous ketones may influence energy balance and recovery during periods of intense training. A study involving athletes undergoing overload training found that those who ingested a ketone drink during recovery maintained energy balance, while the control group slipped into negative energy balance. This suggests that ketones may improve recovery by influencing calorie intake.
Read also: Ketones and Your Health
Caveats and Considerations
Despite the potential benefits, there are several caveats to consider regarding the use of exogenous ketones for weight loss.
Inhibition of Fat Breakdown
The body has a feedback mechanism that slows down the production of ketones if blood ketone levels become excessively high. Therefore, taking ketone supplements may prevent body fat from being used as fuel, at least in the short term.
Caloric Content
Ketones themselves contain calories, approximately four calories per gram, similar to carbohydrates or protein. While a single serving of exogenous ketone salts may contain less than 100 calories, maintaining a state of ketosis requires multiple servings throughout the day. This can add up and may not be worthwhile for weight loss, depending on individual calorie goals.
Side Effects and Safety
Exogenous ketone supplements are generally considered safe, but long-term effects are still unknown. Common side effects, more prevalent with ketone salts, include nausea, diarrhea, and stomach discomfort. Additionally, ketone supplements can have a poor aftertaste.
Moreover, achieving ketosis with ketone salts is not recommended due to the high mineral content. A single serving of ketone salts can provide significant amounts of sodium, magnesium, and calcium, which can be problematic if taken frequently.
Read also: Weight Loss Guide Andalusia, AL
Exogenous Ketones and Athletic Performance
Beyond weight loss, exogenous ketones have shown promise in enhancing athletic performance and recovery.
Glycogen Sparing
Initial excitement surrounded the potential of exogenous ketones to spare glycogen during exercise. However, subsequent research has not consistently supported this claim. It now appears unlikely that exogenous ketone supplementation has a significant glycogen-sparing effect during exercise.
Recovery and Adaptation
Current research focuses on how exogenous ketones might benefit recovery and adaptation in athletes. Studies have shown that ketone supplementation can blunt symptoms of overreaching during intense training, including boosting power output, maintaining maximum heart rate, and reducing stress hormones. Furthermore, post-training ketone supplementation has been shown to improve sleep and increase circulating erythropoietin (EPO) concentrations, a hormone involved in red blood cell production.
Sleep Enhancement
Research indicates post-exercise ketone supplementation improves sleep, which can be impaired during periods of heavy training load.
Potential Benefits Beyond Weight Loss and Athletic Performance
The potential health benefits of exogenous ketones extend beyond weight loss and athletic performance.
Brain Health
Ketones are an important energy source for the brain, especially during energy crises, such as those seen with chronic glucose hypometabolism or after a concussion. They may help protect brain cells against damage due to reactive oxygen species production after a brain injury and may even have some merit for people with Alzheimer’s disease.
Psychiatric Disorders and Epilepsy
Some experts theorize that the metabolism-altering effects of exogenous ketones may help treat psychiatric disorders, such as schizophrenia and bipolar disorder. A 2019 review suggests that exogenous ketones affect levels of certain neurotransmitters within the brain, therefore reducing some of the signs of psychiatric conditions.
Exogenous Ketones and Blood Glucose Control
Exogenous ketone supplementation has shown promise in improving blood glucose control, particularly in individuals with insulin resistance and type 2 diabetes. Studies have demonstrated that acute ketone monoester ingestion can lower the rise in plasma glucose following an oral glucose tolerance test. Furthermore, long-term ketone monoester supplementation has been shown to lower mean daily glucose and postprandial glucose excursions in individuals with overweight/obesity.
The mechanisms underlying the glucose-lowering effect of exogenous ketones are complex and not fully understood. Potential mechanisms include increased insulin secretion, decreased endogenous glucose production, and improved peripheral insulin sensitivity.
The Role of Ketones in Modulating Inflammation and Immune Function
Cellular and rodent studies have demonstrated that ketones, particularly β-OHB, can modulate inflammation by inhibiting the NLRP3 inflammasome activation, leading to decreased production of pro-inflammatory cytokines. These findings suggest that exogenous ketones might be able to ameliorate inflammation in obesity and other inflammatory conditions.
Exogenous Ketones vs. MCT Oil
MCT (medium-chain triglyceride) oil is another supplement often used in conjunction with ketogenic diets. The body can easily break down MCTs into ketones, making them a readily available fuel source. While MCT oil can boost ketone production, it typically won't induce ketosis on its own. MCT oil may be a more cost-effective alternative to exogenous ketones.
How to Use Exogenous Ketones
If you're considering using exogenous ketones, here are some guidelines:
- Timing: Ketone supplements can be taken between meals or before a workout to provide a quick source of ketones. They can also be used to help you get back into ketosis more easily after abandoning the diet for a period.
- Dosage: If you’re using a powdered ketone supplement, try mixing one scoop/serving with about 12 ounces of water, plain almond milk, coffee, or tea. For keto capsules, a typical dose is about 6 capsules daily with 8 ounces of water.
- Duration: You might use exogenous ketones for about 3-5 days while you’re transitioning into ketosis.
- Listen to Your Body: Pay attention to how your body responds to ketone supplementation and adjust your dosage accordingly.