Can Keto Diets Cause Long-Term Harm? A Scientific Analysis
A recent study published in Science Advances suggests that the ketogenic diet (KD) induces harmful cellular changes in multiple organs, raising concerns about its long-term safety. While the study offers valuable insights, it's essential to examine its findings within the broader context of existing research on the ketogenic diet, especially given its short-term nature. This blog will simplify the scientific concepts and refute the study's conclusions by discussing the limitations of using short-term data to predict long-term outcomes and presenting evidence from longer-term studies.
Summary of the Study
The study found that mice on a ketogenic diet showed signs of cellular aging in multiple organs, linked to increased levels of a protein called p53, which is associated with aging and stress. The authors suggest these findings have significant clinical implications for long-term ketogenic diet use.
Simplifying the Science
Short-Term Nature: The study observed mice for just 21 days. Predicting long-term health effects based on such a short period is unreliable because the body can adapt in ways that alter initial responses over time.
Species Differences: What happens in mice doesn't always happen in humans. Mice and humans have different metabolisms, so we can't directly apply mouse study results to people.
Diet Composition: The study used specific types of fats not commonly used in human ketogenic diets. For example, the mice were fed diets high in seed oils, which aren't representative of the diverse fats humans consume on a keto diet.
Evidence from Long-Term Studies
To refute the study's implications, let's look at what longer-term research says about the ketogenic diet.
Cardiovascular Health:
HDL/Triglyceride Ratios: Long-term studies show the ketogenic diet can improve heart health by reducing triglycerides (a type of fat in the blood) and increasing HDL (“good” cholesterol). These changes improve the HDL/triglyceride ratio, a better predictor of heart health than looking at LDL (“bad” cholesterol) alone (Ketogenic.com) (MDPI).
While LDL is the darling of the Statin world and likely your doctor’s favorite heart predictor, there are no studies that show LDL is a reliable factor in determining heart disease risk. In fact, the likelihood that you will have a heart attack with a low LDL level is just as high as if your LDL is elevated!
Kidney Health:
When discussing aging and long-term health the risk of kidney disease from eating too much protein is always thrown in the ring. However, according to Dr. Jason Fung, a kidney specialist, the ketogenic diet can benefit kidney health if managed correctly. Lowering blood sugar and insulin levels can help improve kidney function and reduce damage, especially in diabetics (Frontiers).
And while some long-term studies indicate the ketogenic diet may initially stress the kidneys, it doesn't necessarily cause chronic damage if properly monitored (BioMed Central).
Bone Health:
Children with Epilepsy: Long-term ketogenic diets in children with epilepsy have been linked to risks like bone fractures and growth issues. However, these effects are often due to using unhealthy fats like seed oils, not the ketogenic diet itself (Frontiers).
Adults: A systematic review showed no significant changes in bone density in patients on a ketogenic diet. (Frontiers)
Metabolic Health:
Improved Metabolic Markers: Long-term studies show the ketogenic diet can improve insulin sensitivity (how the body responds to insulin) and lower triglycerides, which reduces the risk of type 2 diabetes and metabolic syndrome (Ketogenic.com) (MDPI).
Mixed Insulin Resistance Results: Some studies report increased insulin resistance in muscles, but muscle insulin resistance can actually improve metabolic flexibility, helping the body switch efficiently between burning fat and carbohydrates (Students 4 Best Evidence).
Do I Need to Do the Ketogenic Diet only Intermittently?
The science is never settled.
So even though long-term human studies suggest that the ketogenic diet can offer significant health benefits, particularly for cardiovascular and metabolic health, we should always be on the lookout for what is next. We can never know if we missed anything if we only see what we believe is true. So, while the recent study raises important questions about the p53 protein long-term, its findings should be viewed with caution due to the short-term nature of the research and its reliance on animal models.
For those considering or currently on a ketogenic diet, it is essential to consult healthcare professionals and consider regular monitoring to ensure the diet remains beneficial in the long run.