We’ve seen our fair share of diet trends in recent years. The latest craze is the ketosis/ketogenic diet or better known as the keto diet. Showing to be popular particularly in the fitness industry, for endurance athletes and ironmen, and used as fat burning strategy. But is keto really for you? Can it be harmful? What are the pros and cons?
Ketosis is a metabolic state where the body produces ketone bodies in the liver to supply fuel/energy for cells including the brain, which relies on glucose. This keto-adaptation shifts your body to rely more on fat-based sources for energy, rather than glucose, which is the bodies preferred energy source. This increases fat oxidation and breakdown of fats into the bloodstream to be used as energy. Ketosis is not the same as diabetic ketoacidosis that can occur in uncontrolled diabetes.
The keto diet is based on a low carb, high fat and moderate protein diet plan. The macros are usually around 50-60% fat, 20-30% protein, 10-30% carbohydrate but can be as strict as 70-90% fat, 20-30% protein and 10% carbohydrate. This means the diet needs to be properly tracked and measured to ensure sufficient intake of macros and calories. The diet usually consists of plenty of nutrient-dense low carb vegetables, good quality protein sources, and healthy fats with high amounts of MCT fats (such as coconut oil and milk) and other healthy fats such as avocados, olives and olive oil, seeds, nuts, fatty fish, and grass-fed meats. Carbs are low but not completely restricted, usually consisting of starches like sweet potato. Individuals who train regularly or intensely often need more carbs whilst still being able to keep in a ketosis.
Studies have shown when ketosis is done correctly it can have positive health benefits such as:
• Increase fat oxidation and aid fat loss
• Reduce inflammation
• Improve blood glucose levels and enhance insulin sensitivity
• Increase satiety and decrease food cravings
• Improve energy levels
• Improve athletic performance including oxygen capacity, enhanced blood flow and increased endurance
• May reduce the risk of several chronic diseases
A high-quality diet is integral to the safety and effectiveness of keto diets. There are several risks to consider, and as such with any diet, ketosis should be managed under supervision of a health practitioner such as a nutritionist. Health risks to consider include:
1. Increased acidity – the keto metabolic process causes waste by-products, hydrogen and CO2, to be released, which the body then must eliminate usually through breath. This risks a buildup in the blood which decreases the blood pH levels, making the body more acidic and at risk of damage to organs and tissues. Ensure adequate intake of alkaline foods to buffer this, including plenty of leafy greens and consider a spirulina or greens powder supplement.
2. Thyroid and metabolic issues – extremely low carb diets can cause an underactive thyroid and slow metabolic rate. Not want you want when trying to burn fat. Carbs are used by the thyroid to convert inactive thyroid hormones to active thyroid hormone. Ensure carbohydrates are not completely restricted, and time them around your training. Include thyroid supporting nutrients rich in iodine and selenium such as sea vegetables and brazil nuts.
3 Increased triglycerides – if dietary fats come from poor sources, this can raise triglyceride levels and increase the risk of cardiovascular diseases. Avoid high amounts of roasted seeds or nuts, vegetables oils, nut butters or heated oils, and BBQ meats, as the heating process damages the oils in these foods.
4. Inflammation – high cholesterol can be in part genetic, part environmental, part dietary, which is why it’s important to monitor particularly when on any restrictive or high-fat diet. If you are eating a lot of high-fat foods, even from good sources but your lifestyle is causing excess inflammation (from stress, too much exercise and little recovery, lack of sleep, exposure to toxins and pollutants), this can cause cholesterol to rise. Whilst some cholesterol is vital to health, particularly for the synthesis of steroid hormones, prolonged too high cholesterol levels can cause damage. High cholesterol and increased blood glucose levels can put you at risk of blood vessel damage and plaque formation, contributing to atherosclerosis.
5. Gut health – restricting carbs without having an adequate intake of vegetables and fruits can lower intake of fiber, leading to gastrointestinal disturbances. Fiber is essential for digestive and colon health, improves laxation, and feeds good bacteria in the gut. Low fiber intake can put you at risk of chronic diseases including type 2 diabetes, cardiovascular disease, and colon cancer. Gut health is vital to optimal health.
These are just some of the things to consider with keto diets. As with any diet, it is important to understand the risks and benefits, and consult a health professional who has a full understanding of nutrition, as well as taking into consideration you as an individual, your lifestyle and goals.