Keto's Long-Term Effects: Does It Really Work?

The ketogenic, or keto, diet is a very low-carbohydrate, high-fat diet. It is advertised as a weight-loss wonder, but it is actually a medical diet that comes with serious risks. While it can lead to quick weight loss, the long-term effects of the keto diet are less clear.

The keto diet is based on the idea that by cutting out carbs, your body starts to turn to fats for fuel. This state is called ketosis. When you reach ketosis, you're using fat as your primary fuel source. However, getting into ketosis can be challenging and may take several days. During this transition period, you may experience what is known as the keto flu, which includes symptoms such as extreme fatigue and foggy-headedness.

While the keto diet can lead to weight loss, it is not a miracle diet and may not be effective for everyone. It is also not a long-term solution as it is very restrictive and can be difficult to stick to. There are concerns about the potential health risks of a long-term keto diet, including nutrient deficiencies, metabolic dysfunction, and increased risk of heart disease and cancer. Additionally, it may affect athletic performance, especially for high-intensity activities.

Overall, the keto diet may be beneficial for some people in the short term, but the long-term effects are still unclear and there are potential health risks associated with it. It is important to consult with a healthcare professional before starting any restrictive diet like the keto diet.

Weight loss

The keto diet is advertised as a weight-loss wonder, but it is actually a medical diet that comes with serious risks. It is best to use this diet only as a short-term dietary change to jump-start weight reduction. The keto diet is a very low-carb, high-fat eating plan that has been shown to offer various health benefits, including weight loss.

The keto diet aims to force your body into using a different type of fuel. Instead of relying on sugar (glucose) that comes from carbohydrates (grains, legumes, vegetables, and fruits), the keto diet relies on ketone bodies, a type of fuel that the liver produces from stored fat. Burning fat seems like an ideal way to lose pounds, but getting the liver to make ketone bodies is tricky. It requires that you deprive yourself of carbohydrates—fewer than 20 to 50 grams of carbs per day. It typically takes a few days to reach a state of ketosis.

The keto diet has been associated with weight loss, though the exact mechanisms remain unclear. Studies suggest that weight loss related to the keto diet is likely due to a calorie deficit, a reduction in hunger levels, and water weight loss.

Research indicates that the keto diet can help shed body fat, but long-term studies supporting its effectiveness are lacking. One study in 20 people with obesity following the keto diet associated this way of eating with reduced food and alcohol cravings. Another study in 17 men with obesity or excess weight found that the keto diet was associated with a small increase in the number of calories burned, although this did not lead to increased body fat losses compared with a traditional baseline diet.

One of the major downsides of the keto diet, especially for weight loss, is long-term sustainability. Considering that the diet is quite restrictive, some people may find it difficult to adhere to. It particularly creates challenges when dining out or gathering with family and friends for the holidays, as a new way of eating must be adopted, potentially affecting social interactions. Furthermore, studies on the health effects of following the keto diet for long periods are lacking.

A ketogenic diet has numerous risks. Top of the list: it's high in saturated fat, which is linked to heart disease. And indeed, the keto diet is associated with an increase in "bad" LDL cholesterol, which is also linked to heart disease. Other potential keto risks include nutrient deficiency, liver problems, kidney problems, constipation, and fuzzy thinking and mood swings.

When following a keto diet for weight loss purposes, some other factors also need to be kept in mind to ensure progress. It may help to keep track of exactly how many carbs you are consuming daily. This helps ensure that you enter ketosis relatively quickly and avoid some of the symptoms associated with the "keto flu," which is a group of symptoms, including headaches and brain fog, related to starting a keto diet. For most people, eating less than 50 grams of carbs per day should be sufficient to stimulate ketosis.

Sleep is an often-overlooked aspect of any diet. Studies show that a lack of sleep and chronic stress can negatively impact weight loss outcomes, and this holds true when following the keto diet. Ensuring that you take time to unwind and get at least seven hours of sleep per night can help support the benefits of a ketogenic diet.

While the keto diet alone may provide weight loss, combining it with a proper exercise regimen can enhance this effect. When adapted to the diet, your body can use fat as its primary fuel source for exercise. Studies suggest that this is most beneficial in endurance-based sports. It's important to note that you should be well-adjusted to the keto diet before performing any moderately intense exercise to avoid negative side effects.

Health benefits

While the keto diet has been hailed as a solution for weight loss and diabetes management, its long-term health benefits are less clear. Here are some potential health benefits of the keto diet:

Weight Loss

The keto diet can lead to quick weight loss, especially in obese individuals. By drastically reducing carbohydrate intake, the body is forced to break down fat for energy, resulting in reduced body weight and body mass index. However, this weight loss may be partly due to the release of stored water and reduced calorie intake.

Improved Blood Sugar Control

The keto diet has been shown to improve blood sugar control in patients with type 2 diabetes, at least in the short term. This is because the body uses fat instead of glucose as its primary fuel source.

Reduced Risk Factors for Heart Disease

A ketogenic diet has been found to decrease total cholesterol, low-density lipoprotein (LDL or "bad") cholesterol, and triglyceride levels, while increasing high-density lipoprotein (HDL or "good") cholesterol levels. These changes can reduce the risk factors associated with heart disease.

Neuroprotective Effects

The keto diet has been used to treat drug-resistant epilepsy, especially in children, and there is evidence that it reduces seizures. This has raised questions about its potential benefits for other brain disorders, such as Parkinson's, Alzheimer's, and multiple sclerosis.

Improved Gut Health

The keto diet restricts some of the best sources of fiber, which is crucial for a healthy gut microbiome. However, non-starchy vegetables like bell peppers, zucchini, cauliflower, and broccoli, which are allowed on the keto diet, can provide some fiber.

While the keto diet may offer these potential health benefits, it is important to note that it can also lead to long-term health risks, including vitamin and mineral deficiencies, negative effects on athletic performance, and an increased risk of heart disease, cancer, and Alzheimer's disease. It is always recommended to consult with a healthcare professional before starting any restrictive diet like keto to ensure it is safe and appropriate for your individual needs and health goals.

Nutrient deficiencies

The keto diet is associated with an increased risk of nutrient deficiencies. The diet's restrictive nature means that followers may not be getting all the essential vitamins and minerals needed to maintain a healthy diet.

Micronutrients

According to Harvard Health, a keto diet may result in deficiencies in micronutrients such as selenium, magnesium, phosphorus, and vitamins B and C. Quest Health and MedlinePlus also highlight the risk of vitamin and mineral deficiencies on a keto diet.

Fiber

The keto diet restricts fiber-rich foods such as whole grains, legumes, and fruits

Athletic performance

The ketogenic diet has become popular among endurance athletes as a performance enhancer. The diet prescribes a significant reduction in carbohydrate intake, which facilitates physiological changes that promote the utilization of ketones. This diet has been shown to reduce lactate accumulation after exercise, contributing to enhanced recovery. However, the keto diet's impact on athletic performance is mixed, and more research is needed to understand its effects fully.

Benefits of the Keto Diet for Athletes

The keto diet may improve athletic performance by:

• Enhancing fat-burning and weight loss: The keto diet can increase fat burning during submaximal exercise, leading to lower body fat and a better power-to-weight ratio.
• Reducing reliance on muscle glycogen: As the body relies more on fat for fuel, athletes may be able to train and race for longer distances without "hitting the wall" or experiencing energy depletion.
• Reducing inflammation: Prolonged, heavy, and vigorous exercise can trigger an inflammatory response, and the keto diet's anti-inflammatory properties may benefit active individuals.
• Improving digestive issues: The keto diet may be better tolerated by athletes with irritable bowel syndrome or other digestive issues, helping to prevent GI symptoms during exercise.
• Enhancing overall health: The keto diet has been shown to reduce body fat, type 2 diabetes, and metabolic syndrome, which may positively impact athletic performance and overall well-being.

Potential Drawbacks of the Keto Diet for Athletes

However, there are also potential drawbacks and considerations for athletes following the keto diet:

• Performance in high-intensity sports: The keto diet may not be ideal for athletes involved in high-intensity, short-duration sports, as it may lead to decreased anaerobic exercise performance. These athletes rely on carbohydrates as their primary fuel source, and the keto diet may cause a higher perceived effort of exertion, higher heart rate, and lower power during these types of exercises.
• Muscle mass gain: The keto diet is moderate, not high, in protein, which is important for muscle building. Athletes looking to gain muscle mass may not benefit from the keto diet as it may hinder their ability to build muscle effectively.
• Nutritional deficiencies: The keto diet restricts many nutrient-dense foods, and athletes following this diet may need to supplement with additional electrolytes, potassium, magnesium, vitamins A and C, and folate.
• Social and practical challenges: The keto diet can be difficult to sustain over the long term due to social eating challenges and limited food choices. Additionally, the initial transition to the keto diet can cause side effects such as poor energy, mental function, sleep issues, nausea, and digestive discomfort.

Practical Recommendations for Athletes on the Keto Diet

For athletes considering the keto diet, here are some practical recommendations:

• Timing of carbohydrate intake: Consume carbohydrates before and after exercise to help your body prepare for and recover from intense activity.
• Experiment with lower carb intake: If you're unsure about fully committing to the keto diet, try lowering your carb intake modestly and monitoring its impact on your performance.
• Allow for an adaptation period: It takes time to adapt to the keto diet, and you may experience the "keto flu" in the first week, so don't embark on this diet right before an important event or competition.
• Work with a sports dietitian: Consult a sports dietitian to develop a personalized eating pattern that considers your specific goals and potential nutrient deficits.
• Consider a modified keto approach: If the strict keto diet seems too extreme, a modified keto diet with 30% protein, 55% fat, and 15% carbs may be a more sustainable option. This allows for the inclusion of some legumes, starchy veggies, fruits, nuts, and seeds while still promoting weight loss and providing a wider range of nutrients.

Case Study: Ben Greenfield

Ben Greenfield, a top-ranked amateur triathlete, followed a keto diet for 12 months, consisting of 80-90% fat and 5-10% carbohydrates. He continued to consume some carbohydrates during races, especially during high-intensity surges, and supplemented with proteins, amino acids, and medium-chain triglycerides. Greenfield's muscle carbohydrate storage and fat-burning capacity improved, and he was able to maintain similar race speeds while increasing fat burning and reducing blood sugar fluctuations.

In conclusion, while the keto diet may offer some benefits for endurance athletes, particularly in terms of fat burning and weight loss, it may not be ideal for high-intensity sports or those looking to gain muscle mass. More research is needed to fully understand the long-term effects of the keto diet on athletic performance, and athletes should consult with sports dietitians to ensure their nutritional needs are met.

Longevity

Keto and Longevity

The ketogenic diet is a very low-carb, high-fat diet. While it may lead to short-term weight loss for some people, restrictive diets like keto can be difficult to stick to and many people regain any lost weight once they come off it.

There is limited research on the long-term effects of the keto diet on humans, but studies on mice have shown that a ketogenic diet can increase longevity and healthspan. One study found that mice fed a ketogenic diet had a 13.6% increase in median lifespan compared to a control group. The mice on the ketogenic diet also displayed better memory, coordination, strength, and endurance, and had better-preserved motor function, memory, and muscle mass in old age.

However, there are also potential health risks associated with long-term adherence to the keto diet. Here are some points to consider:

• Vitamin and Mineral Deficiencies: Restricting carbohydrates to 50 grams or less per day means cutting out not just unhealthy foods like white bread and refined sugar but also fruits and certain vegetables, which can lead to vitamin and mineral deficiencies over time.
• Impact on Athletic Performance: Some researchers are concerned that the keto diet could sabotage strength and fitness in athletes. A 2019 study found that participants performed worse on high-intensity cycling and running tasks after four days on a ketogenic diet compared to those on a high-carb diet.
• Weight Regain: The strict nature of the keto diet can make it challenging to follow long-term, and people may transition to a more relaxed form of keto that allows more carbohydrates. This can lead to weight regain, and the type of weight gained back may be mostly fat, which can affect metabolism and make it harder to lose weight again.
• Blood Vessel Damage: A 2019 study found that indulging in a high-sugar treat while on a high-fat, low-carb diet can damage blood vessels.
• Heart and Artery Health: Health experts worry about the long-term impact of a keto-style diet on the heart and arteries. Studies have found that people on low-carb diets are more likely to develop atrial fibrillation and have an increased risk of dying from cancer and all other causes during the study period.

Overall, while the keto diet may offer some potential benefits for longevity, there are also risks to consider. More long-term research is needed to fully understand the effects of the keto diet on human health and longevity. In the meantime, it is important to consult with a healthcare professional before starting any restrictive diet like keto to ensure it is safe and appropriate for your individual needs.

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