Recent research on mice suggests that following a ketogenic (keto) diet may lead to faster aging in internal organs such as the heart and kidneys. A keto diet is high in fat and low in carbohydrates, and while it’s known for rapid weight loss, there are concerns about its long-term effects on health.
Researchers from UTHealth San Antonio explored how keto diets impact cellular aging in mice, and their findings raise important questions about the diet’s impact on human health.
What is a Ketogenic Diet?
A ketogenic diet emphasizes high fat intake, moderate protein consumption, and a very low carbohydrate intake. Typically, those on a keto diet consume:
- 55–60% of their calories from fats,
- 30–35% from proteins, and
- 5–10% from carbohydrates, which equates to around 20 to 50 grams of carbs per day.
To put this into perspective, the FDA recommends that individuals consume far fewer saturated fats (less than 10% of total calories), favoring healthier unsaturated fats from sources such as fish, avocados, and nuts. Additionally, the FDA suggests a much higher carbohydrate intake of about 275 grams daily.
The Study: Keto Diet and Organ Aging in Mice
To investigate how keto diets impact organ health, researchers tested the effects of high-fat diets on mice. The study divided the mice into two groups: a control group and a test group fed a high-fat diet made mostly of Crisco. The Crisco group consumed 90.5% of their calories from fats, with the majority of those fats being unsaturated.
The mice started their diets at around 35 to 42 days old, continuing for either 7 or 21 days. After this period, researchers examined the health of the mice, paying particular attention to cellular aging in their organs.
Keto Diet Accelerates Cellular Aging
The researchers found that mice on the ketogenic diet showed signs of accelerated aging in major organs like the heart and kidneys. Specifically, they detected an accumulation of senescent cells, which are older cells that stop dividing but do not die off as they should. These cells can cause inflammation and damage to surrounding tissues.
According to the National Institutes of Health, the buildup of senescent cells is associated with aging and various diseases. When these cells fail to die, they can lead to organ dysfunction and, in some cases, contribute to the formation of tumors.
Different Types of Keto Diets, Same Results
To explore further, the scientists also tested a second group of mice on a different type of keto diet, this time using cocoa butter, which has a higher saturated fat content than Crisco. The results were similar, with mice on the cocoa butter diet also showing signs of organ damage and cellular aging.
The researchers found that two proteins, AMPK and p53, played a role in this process of cellular senescence. Blocking these proteins reduced the level of cellular aging, indicating that targeting these pathways could mitigate the negative effects of keto diets on organ health.
Is Cellular Aging Reversible?
Interestingly, the study revealed that the signs of cellular aging could diminish once the mice stopped following the ketogenic diet. This suggests that while the keto diet may cause damage, there are ways to manage or potentially reverse its effects, either through medications that target specific proteins or by using the diet intermittently.
How Does This Apply to Humans?
Although this research was conducted on mice, it raises significant questions about how keto diets might affect human health, particularly in the long term. Experts like Scott Keatley, a dietician based in New York City, emphasize the importance of understanding the long-term risks associated with keto diets. He points out that while the diet can be effective for weight loss and epilepsy management, its effects on organ aging are still unclear.
Keatley highlights the need for careful consideration, particularly for individuals with pre-existing health conditions. He also stresses the importance of conducting human studies over longer periods to fully understand how keto diets impact organs like the heart and kidneys.
Steve Gendron, PhD, an expert in immunology and endocrinology, agrees. He argues that we need to follow individuals on keto diets for extended periods—years, not just months—to truly see how these diets affect overall health. Gendron also calls for more diverse studies, comparing different types of ketogenic diets and their impacts on various health issues.
Why Is This Study Important?
This research provides a deeper understanding of the potential risks associated with long-term ketogenic diets. While keto diets may offer short-term benefits like rapid weight loss and improved epilepsy control, they might come at a cost to organ health, particularly in the heart and kidneys.
The discovery that ketogenic diets could accelerate cellular aging in organs raises concerns about recommending such diets without medical guidance. Given the potential for organ damage, it’s important for individuals to consider how long they stay on the keto diet and to monitor their health regularly.
Recommendations for Those Considering Keto
For those thinking about starting a ketogenic diet, this study underscores the importance of medical supervision. Anyone with existing heart or kidney issues should be particularly cautious and consult their healthcare provider before beginning such a diet. Even individuals in good health should carefully consider the duration of the diet and focus on incorporating healthy fats, like those found in fish, nuts, and avocados.
Conclusion
While ketogenic diets can provide benefits for weight loss and certain medical conditions, the long-term effects on organs like the heart and kidneys are still not fully understood. The recent research on mice indicates that keto diets might accelerate cellular aging in these organs, potentially leading to inflammation, damage, and other health issues.
Future studies involving humans will be essential to confirm these findings and to understand the full range of effects that keto diets have on health. For now, anyone considering a ketogenic diet should do so with caution and seek advice from a medical professional.
