ABOUT PUTTING CHILDREN ON A POPULAR DIET. THE AMERICAN ACADEMY OF PEDIATRICS IS SAYING KETO FOR KIDS COULD BE DANGEROUS. I HAVEN鈥橳 EVEN HEARD ABOUT THAT. THERE YOU GO. SO I鈥橫 GLAD YOU鈥橰E HERE. DR. TODD ELLERIN, THE VICE CHAIR OF MEDICINE AT SOUTH SHORE HEALTH. LET鈥橲 TALK ABOUT IT. ALL RIGHT. DR. T TO BE HERE AS YOU KNOW, SOME ADULTS, SOME ADULTS USE THAT THE KETO DIET USE A HIGH FAT ALMOST NO CARB DIET TO LOSE WEIGHT AND REDUCE THEIR RISK FOR DIABETES. BUT IT鈥橲 CONTROVERSIAL. SO WHAT ARE SOME OF THE CONCERNS FOR ADULTS? LET鈥橲 START THERE RIGHT. WELL, EDDIE, YOU鈥橰E RIGHT. THERE ARE SOME BENEFITS TO THIS. YOU CAN HAVE WEIGHT LOSS SOMETIMES THERE鈥橲 SOME ADVANTAGES TO WITH YOUR SUGAR METABOLISM. BUT HERE鈥橲 THE PROBLEM. FIRST OF ALL, THERE AREN鈥橳 STUDIES THAT HAVE LOOKED AT LONG TERM IN ADULTS AND ALSO WITH CHILDREN. AND THE OTHER PROBLEM IS TOLERABILITY. WHEN YOU鈥橰E IN A STATE OF LOW CARBOHYDRATES, WHAT WE CALL POTENTIAL KETOSIS, YOU REALLY CAN FEEL HEADACHES AND FATIGUE. YOU CAN BE IRRITABLE, YOU KNOW, AND THESE TYPE OF THINGS DO MAKE IT CHALLENGING TO STAY ON THAT. AND REMEMBER, CARBOHYDRATES ARE THE BASIC ENERGY CURRENCY THAT WE USE IN OUR EVERYDAY LIFE. SO LET鈥橲 TALK ABOUT THE KIDS. WHY DOES THE AMERICAN ACADEMY OF PEDIATRICIANS THINK THAT THESE KETO DIETS COULD BE EVEN MORE RISKY? WELL, MARIA, YOU KNOW, IT鈥橲 A VERY IMPORTANT QUESTION. AND REMEMBER, OUR KIDS AREN鈥橳 JUST LITTLE ADULTS. REMEMBER, NUMBER ONE, WHAT HAS BEEN SHOWN IS IF YOU RESTRICT CARBOHYDRATE RATES TOO MUCH, YOU CAN ACTUALLY HAVE PROBLEMS WITH GROWTH. SO, YOU KNOW, WE鈥橰E KIDS. YOU WANT THEM TO GROW NORMALLY. THAT鈥橲 NUMBER ONE. ANOTHER POINT IS THAT THEY CAN HAVE NUTRITIONAL DEFICIENCIES, EASY THINGS. THEIR B VITAMINS, FOR EXAMPLE. A LOT OF THAT COME FROM CARBOHYDRATES. AND THE LAST POINT IS FIBER AS WELL. A LOT OF THE GOOD CARBOHYDRATE THAT鈥橲 FIBER CAN KEEP YOU REGULAR. IT鈥橲 IMPORTANT FOR GUT HEALTH AND OTHERS. IT CAN ALSO HELP WITH SUGAR METABOLISM. I WANT TO SAY ONE MORE THING. CARBON HYDRATES ARE NOT ONE ENTITY. THERE鈥橲 GOOD CARBOHYDRATES LIKE WHOLE GRAINS, YOU KNOW, THINGS LIKE BROWN RICE, THINGS LIKE LEGUMES, WHICH ARE BEANS ARE VERY IMPORTANT. AND THEN THERE鈥橲 THE BAD CARBOHYDRATES, WHICH YOU CAN IMAGINE THE THINGS LIKE LIKE WHITE BREAD. AND MOST IMPORTANTLY, SUGARY DRINKS, PROCESSED FOODS LIKE COOKIES AND CHIPS. THOSE ARE THE THINGS WE WANT TO DE-EMPHASIZE. EMPHASIZE THE HEALTHIER CARBS. AND DR. TIM, WE KNOW THAT CHILDHOOD OBESITY AND DIABETES AS WELL, IT鈥橲 A GROWING THREAT FOR KIDS. SO WHAT KIND OF FOOD PLAN DOES THAT? DOES THE ACADEMY OF PEDIATRICIANS RECOMMEND INSTEAD? LET鈥橲 TALK ABOUT WHAT THEY RECOMMEND. RIGHT. FIRST OF ALL, WHAT THEY DON鈥橳 RECOMMEND IS COMPLETELY RESTRICTING CARBOHYDRATE. IT鈥橲 THEY鈥橰E SAYING YOU HAVE TO HAVE AT LEAST 26% OF YOUR CALORIES SHOULD BE COMING FROM CARBOHYDRATES. THEY EMPHASIZE THE GOOD CARBOHYDRATES, NOT THE BAD ONES. LIKE I MENTIONED BEFORE. WHAT THEY鈥橰E REALLY SAYING ULTIMATELY IS THINK ABOUT A MEDITERRANEAN DIET. NOW, WHAT IS MEDITERRANEAN DIET? EMPHASIZE IT EMPHASIZES LEAN PROTEINS LIKE SEA FOODS, LESS RED MEAT. IT EMPHASIZES THINGS LIKE NUTS AND SOME OF THOSE HEALTHIER CARBOHYDRATES, AS WELL AS HEALTHY FATS AS WELL. IT鈥橲, I鈥橠 SAY MEDITERRANEAN IS MORE OF A BALANCED DIET. IN ESSENCE, THEY DO SAY THAT IN SOME KIDS WITH DIABETES, SOME RESTRICTION OF CARBOHYDRATES TO A MODERATE LEVEL IS OKAY. BUT REMEMBER, YOU ALWAYS WANT TO DO THIS IN ACCORDANCE WITH YOUR PEDIATRICIAN OR OR OR DIABETIC TEAM. SO IT鈥橲 CHALLENGING AND NUANCED. YEAH, THAT鈥橲 GREAT ADVICE. BUT I COULD NEVER GET MY KIDS TO EAT FISH. NO WAY. OH, REALLY? NO WAY. WE ATE A MEDITERRANEAN. EDDIE, DON鈥橳 GIVE UP. IT鈥橲 NOT TOO LATE. SMART MAN.
Scientists find low-calorie keto diet slows aging鈥攂ut is it really good for you?
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Updated: 3:37 PM CDT Apr 13, 2025
Obesity has been thoroughly linked to a higher epigenetic age (drivers of modifications to DNA that may lead to chronic illness and, ultimately, a shorter lifespan). A new study found that a very low-calorie ketogenic diet (VLCKD) may both aid in weight loss and reverse the epigenetic age of participants with obesity by six years鈥攚hile also lowering their risk of conditions like type 2 diabetes and cardiovascular disease. But experts have mixed feelings on the restrictive diet. The study, conducted in Spain and published in Nutrients, compared two groups鈥攖hose with obesity and those with a 鈥渘ormal鈥� weight. Researchers measured biological age with epigenetic clocks (devices that use blood samples to analyze DNA) at the study鈥檚 starting point, after 30 days, and again after 180 days. For at least the first 30 days, the group with obesity followed a VLCKD of 600 to 800 calories structured after the medically monitored commercial weight loss program called the PronoKal Method. By the end of the 180 days, there was an unspecified progressive reintroduction of food and increased calories. (Typically, the method ends with a low-calorie diet of 800 to 1500 calories per day.) The VLCKD phase helped participants accomplish ketosis, which is the metabolic process triggered by a low-carb diet that encourages the body to burn fat for energy instead of carbohydrates. Such a process is thought to be at least partially responsible for the study鈥檚 results. Even so, it鈥檚 important to note that a VLCKD is not enough calories to sustain life for the average person and is not recommended. In fact, experts warn against it. 鈥淚n my experience, patients are not able to stay on a low-calorie ketogenic diet for an extended period of time,鈥� says Meghan Garcia-Webb, M.D., a physician triple board-certified in internal medicine, lifestyle medicine, and obesity medicine. 鈥淚t can set them up for another cycle of yo-yo dieting, and in general, I don鈥檛 recommend it.鈥� What about the diet helped slow down aging, exactly?The study suggests that a number of factors could have contributed to the reversal of epigenetic age in obese participants. Firstly, it appears that ketosis played a significant role, which 鈥渦nderscores the diet鈥檚 potential role in promoting overall health and longevity,鈥� says Trista Best, M.P.H., R.D., L.D., a registered dietitian at The Canada Diet. Researchers also noted that levels of beta-hydroxybutyrate, a byproduct of ketosis, may have also contributed to the changes, as it has been found to boost antioxidant capacity, improve insulin sensitivity, protect brain health, and more. Decreased body mass index due to weight loss also may have played a part, as may have an improved gut microbiome, the study reported. Limitations to the study鈥檚 findings Dr. Garcia-Webb points out that the study was quite small and 鈥渇indings are limited and do not assert direct causation or generalizability to a broader population.鈥� Even so, she finds the results 鈥渋nteresting鈥� because, compared to studies that look at the epigenetic aging process after bariatric weight loss surgery, a VLCKD achieved a greater slowdown in aging, 鈥渨hich suggests the effect may be more linked to the nutritional ketosis and diet as opposed to just the weight loss itself.鈥滲est adds that 鈥渋t鈥檚 essential to approach these findings with caution, considering individual variability and the need for personalized dietary interventions.鈥� Plus, the extreme dietary restrictions associated with the diet can be detrimental to some, and study participants were monitored.All participants were European caucasians. People with pregnancy, substance abuse, or chronic medication use (except for anti-diabetic therapy) were excluded. It鈥檚 unclear if participants remained on a low-calorie diet after research concluded, or if they gained back any weight.Dangers of a very low-calorie keto dietHaving between 600 and 800 calories is about as extreme as low-calorie diets get, which poses risk of not meeting nutrient needs (keto seriously cuts back on the entire food category of carbohydrates, after all), muscle loss, mental fog, and gallstones, according to the Academy of Nutrition and Dietetics. Keto side effects also may include keto flu (short-term flu-like symptoms linked to those starting a keto diet), constipation, diarrhea, dehydration, fatigue, and kidney and heart health challenges.鈥淎ny dietary change patients make, I want them to be able to continue doing for decades,鈥� Dr. Garcia-Webb adds. 鈥淚f someone can鈥檛 see themselves doing a low-calorie ketogenic diet when they are 80, then I wouldn鈥檛 advise starting now.鈥� She adds that long-term keto eating also significantly increases the risk of high cholesterol if patients eat a lot of animal-based saturated fats. And again, such restrictive eating is not ideal.In other words, there are different ways to lose weight and become healthier that don鈥檛 run the same risks as the diet followed in this study. 鈥淧eople can achieve a healthier body with less extreme measures that provide a more enjoyable, sustainable quality of life,鈥� Dr. Garcia-Webb concludes. 鈥淭here鈥檚 less utility to living longer if people are miserable.鈥�
Obesity has been thoroughly linked to a higher (drivers of modifications to DNA that may lead to chronic illness and, ultimately, a shorter lifespan).
A new study found that a very low-calorie ketogenic diet (VLCKD) may both aid in and reverse the epigenetic age of participants with obesity by six years鈥攚hile also lowering their risk of conditions like type 2 diabetes and cardiovascular disease. But experts have mixed feelings on the restrictive diet.
The study, conducted in Spain and published in , compared two groups鈥攖hose with obesity and those with a 鈥渘ormal鈥� weight. Researchers measured biological age with epigenetic clocks (devices that use blood samples to analyze DNA) at the study鈥檚 starting point, after 30 days, and again after 180 days.
For at least the first 30 days, the group with obesity followed a VLCKD of 600 to 800 calories structured after the medically monitored commercial weight loss program called the . By the end of the 180 days, there was an unspecified progressive reintroduction of food and increased calories. (Typically, the method ends with a low-calorie diet of 800 to 1500 calories per day.)
The VLCKD phase helped participants accomplish ketosis, which is the metabolic process triggered by a low-carb diet that encourages the body to burn fat for energy instead of carbohydrates. Such a process is thought to be at least partially responsible for the study鈥檚 results. Even so, it鈥檚 important to note that a VLCKD is not enough calories to sustain life for the average person and is not recommended. In fact, experts warn against it.
鈥淚n my experience, patients are not able to stay on a low-calorie ketogenic diet for an extended period of time,鈥� says Meghan Garcia-Webb, M.D., a physician triple board-certified in internal medicine, lifestyle medicine, and obesity medicine. 鈥淚t can set them up for another cycle of yo-yo dieting, and in general, I don鈥檛 recommend it.鈥�
What about the diet helped slow down aging, exactly?
The study suggests that a number of factors could have contributed to the reversal of epigenetic age in obese participants. Firstly, it appears that ketosis played a significant role, which 鈥渦nderscores the diet鈥檚 potential role in promoting overall health and longevity,鈥� says , a registered dietitian at The Canada Diet. Researchers also noted that levels of beta-hydroxybutyrate, a byproduct of ketosis, may have also contributed to the changes, as it has been found to , , , and more. Decreased body mass index due to weight loss also may have played a part, as may have an improved gut microbiome, the study reported.
Limitations to the study鈥檚 findings
Dr. Garcia-Webb points out that the study was quite small and 鈥渇indings are limited and do not assert direct causation or generalizability to a broader population.鈥� Even so, she finds the results 鈥渋nteresting鈥� because, compared to that look at the epigenetic aging process after bariatric weight loss surgery, a VLCKD achieved a greater slowdown in aging, 鈥渨hich suggests the effect may be more linked to the nutritional ketosis and diet as opposed to just the weight loss itself.鈥�
Best adds that 鈥渋t鈥檚 essential to approach these findings with caution, considering individual variability and the need for personalized dietary interventions.鈥� Plus, the extreme dietary restrictions associated with the diet can be detrimental to some, and study participants were monitored.
All participants were European caucasians. People with pregnancy, substance abuse, or chronic medication use (except for anti-diabetic therapy) were excluded. It鈥檚 unclear if participants remained on a low-calorie diet after research concluded, or if they gained back any weight.
Dangers of a very low-calorie keto diet
Having between 600 and 800 calories is about as extreme as low-calorie diets get, which poses risk of not meeting nutrient needs (keto seriously cuts back on the entire food category of carbohydrates, after all), muscle loss, mental fog, and gallstones, according to the . also may include (short-term flu-like symptoms linked to those starting a keto diet), constipation, diarrhea, dehydration, fatigue, and kidney and heart health challenges.
鈥淎ny dietary change patients make, I want them to be able to continue doing for decades,鈥� Dr. Garcia-Webb adds. 鈥淚f someone can鈥檛 see themselves doing a low-calorie ketogenic diet when they are 80, then I wouldn鈥檛 advise starting now.鈥� She adds that long-term keto eating also significantly increases the risk of high cholesterol if patients eat a lot of animal-based saturated fats. And again, such restrictive eating is not ideal.
In other words, there are different ways to lose weight and become healthier that don鈥檛 run the same risks as the diet followed in this study. 鈥淧eople can achieve a healthier body with less extreme measures that provide a more enjoyable, sustainable quality of life,鈥� Dr. Garcia-Webb concludes. 鈥淭here鈥檚 less utility to living longer if people are miserable.鈥�
