Ketogenic vs Mediterranean Diets for Aging

Overseen By Sanaa Badour, MD

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: University of Florida

Disqualifiers: Diabetes, Cancer, Cardiovascular disease, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 8

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial compares the ketogenic diet (very low in carbs) and the Mediterranean diet to assess their effects on muscle and bone health in older adults. Researchers aim to determine if these diets can prevent age-related muscle loss while also examining any impact on bones. Participants will follow one of these diets for six weeks. The trial seeks postmenopausal individuals who have maintained a stable weight, are willing to follow dietary guidelines, and live within 30 miles of Gainesville, FL. As an unphased trial, this study allows participants to contribute to important research on diet and aging.

Will I have to stop taking my current medications?

The trial protocol does not specify whether you need to stop taking your current medications. However, if you are on anti-hypertensive medication, you may still be eligible to participate.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research shows that the very low carbohydrate ketogenic diet (VLCKD) is generally easy to follow. Studies have found that people on this diet lose more weight than those on low-fat diets. However, concerns exist about muscle loss. One study found that while participants lost weight and fat, they also lost some muscle. Thus, while the diet aids weight loss, it might not be ideal for maintaining muscle.

Regarding safety, some studies suggest that the VLCKD could affect bone health. Researchers are examining its impact on bone renewal and muscle function, especially in older adults.

The Mediterranean diet, in contrast, is known for its heart benefits. It includes plenty of fruits, vegetables, and healthy fats and does not raise the same concerns about muscle or bone health as the ketogenic diet.

Both diets have pros and cons. The ketogenic diet effectively promotes weight loss but might affect muscles and bones. The Mediterranean diet is balanced and supports heart health. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about comparing the ketogenic and Mediterranean diets for aging because these diets offer unique approaches to nutrition that could impact health differently than standard dietary recommendations. The Mediterranean diet, known for its heart-healthy focus on fruits, vegetables, and healthy fats, may support aging by promoting cardiovascular health and reducing inflammation. Meanwhile, the very low carbohydrate ketogenic diet shifts the body into a state of ketosis, where it burns fat for fuel, which might offer benefits like improved brain health and metabolic function. By studying these diets side-by-side, researchers hope to uncover which dietary approach might better support healthy aging and why.

What evidence suggests that this trial's treatments could be effective for age-related sarcopenia?

This trial will compare the effects of the Mediterranean diet and the very low carbohydrate ketogenic diet on aging. Research has shown that the Mediterranean diet, which participants in one arm of this trial will follow, can greatly benefit older adults. Studies have found it lowers the risk of heart disease and reduces the chance of dying from any cause by 23%. It also helps lower the risk of age-related issues, such as frailty. Participants in another arm of this trial will follow the ketogenic diet. Evidence about the ketogenic diet is mixed; while it might aid in weight and fat loss, it can also lead to muscle loss. Some studies in mice suggest it might benefit brain health, but these results are not yet proven in humans. ^{6 7 8 9 10}

Who Is on the Research Team?

Cora Best, PhD, RDN

Principal Investigator

University of Florida

Are You a Good Fit for This Trial?

This trial is for older adults who are postmenopausal, have had a stable weight and BMI between 20 to <35 kg/m2 over the past year. Participants must live in a permanent home, be willing to eat provided food, follow dietary advice, document their intake, maintain their current weight, own a smartphone for monitoring purposes and attend study visits.

Inclusion Criteria

I am postmenopausal.

Your weight has not changed much in the past year.

Your body mass index (BMI) must be between 20 and 35.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

2 visits (in-person), 1 at-home urine collection

Dietary Intervention

Participants are assigned to either a very low carbohydrate ketogenic diet or a Mediterranean diet for 6 weeks. Meals are provided, and participants receive continuous support from a dietitian.

6 weeks

6 visits (in-person, weekly)

Follow-up

Participants are monitored for safety and effectiveness after the dietary intervention

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Mediterranean Diet
• Very Low Carbohydrate Ketogenic Diet

Trial Overview

The study is testing how two diets affect muscle and bone health in older adults. One group will follow a very low carbohydrate ketogenic diet while another will adhere to a Mediterranean diet. The goal is to see which diet might better prevent muscle decline or impact bone metabolism.

How Is the Trial Designed?

Group I: Very low carbohydrate ketogenic diet for six weeks Experimental Treatment 1 Intervention

Group II: Mediterranean diet for six weeks Active Control 1 Intervention

Who Is Running the Clinical Trial?

University of Florida

Lead Sponsor

Trials

1,428

Recruited

987,000+

National Institute on Aging (NIA)

Collaborator

Trials

1,841

Recruited

28,150,000+

Published Research Related to This Trial

A study on individuals over 70 years old found that following the traditional Greek variant of the Mediterranean diet is linked to a significant 17% reduction in overall mortality for each unit increase in dietary adherence score.

This suggests that a closer adherence to this diet can positively impact life expectancy in elderly populations, highlighting the potential health benefits of traditional dietary patterns.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Survival beyond age 70 in relation to diet. de Groot, LC., van Staveren, WA., Burema, J.[2019]

A Mediterranean diet supplemented with dairy foods significantly reduced systolic and diastolic blood pressure in participants at risk of cardiovascular disease, indicating improved cardiovascular health.

The MedDairy diet also led to favorable changes in cholesterol levels, including higher HDL cholesterol and lower triglycerides, suggesting it may be an effective dietary approach for managing cardiovascular risk factors.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A Mediterranean diet supplemented with dairy foods improves markers of cardiovascular risk: results from the MedDairy randomized controlled trial. Wade, AT., Davis, CR., Dyer, KA., et al.[2023]

In a study of 200 older patients (median age 70) on a ketogenic diet, 67% reported beneficial outcomes, including significant weight loss for 79% of those seeking it, improved glucose control for 54% of those with diabetes, and positive effects on cancer outcomes for 63% of patients pursuing that goal.

While the ketogenic diet showed promise for various health issues in older adults, 15% of participants experienced adverse events, including dyslipidemia and constipation, highlighting the need for careful monitoring in this population.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Can older patients adopt and maintain a ketogenic diet? An observational study in support of clinical trials in older patients. Almodallal, Y., Cook, K., Lammert, LM., et al.[2023]

In a study of 183 hospitalized patients over 65 years old, adherence to the Mediterranean diet (MedDiet) was associated with a significant reduction in hospital length of stay by 0.3 days for each unit increase in MedDiet score.

Higher adherence to the MedDiet also correlated with a 13% decrease in long-term mortality risk, suggesting that this dietary pattern not only improves health outcomes but may also reduce healthcare costs.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of Mediterranean diet on hospital length of stay, medical expenses, and mortality in elderly, hospitalized patients: A 2-year observational study. Lampropoulos, CE., Konsta, M., Dradaki, V., et al.[2021]

The Mediterranean diet, characterized by its balanced intake of macronutrients and micronutrients, is recommended for long-term weight maintenance and health benefits, unlike short-term restrictive diets that are difficult to sustain.

Low-carbohydrate ketogenic diets may pose medical risks, particularly for individuals with obesity, as they can lead to metabolic acidosis and renal issues, potentially reducing life expectancy.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Low-carbohydrate ketogenic diets in body weight control: A recurrent plaguing issue of fad diets? Schutz, Y., Montani, JP., Dulloo, AG.[2021]

The Mediterranean Diet (MedDiet) has been linked to numerous health benefits, particularly in reducing the risk of cardiovascular diseases, metabolic disorders, and cancer, as evidenced by an increase in clinical trials over the last decade.

The diet's positive effects are largely attributed to its anti-inflammatory and antioxidant properties, with strict adherence and specific components like olive oil playing crucial roles in managing obesity and waist circumference.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The Mediterranean Diet: An Update of the Clinical Trials. Finicelli, M., Di Salle, A., Galderisi, U., et al.[2022]

A study of 200 hospitalized patients over 60 years old revealed that 91.5% had unhealthy diets, which were linked to poor clinical outcomes like malnutrition and frailty.

Higher adherence to the Mediterranean diet was associated with shorter hospital stays and better overall health, indicating that improving dietary habits could enhance recovery in older adults.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Adherence to the Mediterranean diet in Turkish hospitalized older adults and its association with hospital clinical outcomes. Ergul, F., Sackan, F., Koc, A., et al.[2022]

This study will evaluate the cardiovascular and cognitive benefits of a modified Mediterranean diet that includes 2-3 servings of fresh, lean pork per week, aiming to make the diet more sustainable for Australian populations.

The trial will involve a 24-week cross-over design with at-risk men and women, measuring various health outcomes such as blood pressure, body composition, and cognitive function, which could provide important insights for preventing cardiovascular disease and dementia.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Including pork in the Mediterranean diet for an Australian population: Protocol for a randomised controlled trial assessing cardiovascular risk and cognitive function. Wade, AT., Davis, CR., Dyer, KA., et al.[2019]

A study of 330 elderly individuals (141 Anglo-Celts and 189 Greek-Australians) found that following the Mediterranean diet principles is linked to a 17% reduction in overall mortality, suggesting its potential benefits for longevity.

The positive impact of the Mediterranean diet on survival was consistent across both cultural groups, indicating its effectiveness regardless of ethnic background in a non-Mediterranean context.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Are the advantages of the Mediterranean diet transferable to other populations? A cohort study in Melbourne, Australia. Kouris-Blazos, A., Gnardellis, C., Wahlqvist, ML., et al.[2021]

In a study of 15,535 middle-aged Spanish university graduates followed for an average of 6.8 years, higher adherence to the Mediterranean diet was linked to a significantly lower risk of death, with hazard ratios of 0.58 for moderate adherence and 0.38 for high adherence.

Each 2-point increase in the Mediterranean Diet Score corresponded to a 28% reduction in the risk of death, suggesting that even among younger adults, following this diet can have important health benefits.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The Mediterranean diet is associated with a reduction in premature mortality among middle-aged adults. Martínez-González, MA., Guillén-Grima, F., De Irala, J., et al.[2023]

A study of 5200 individuals aged 65 and older found that greater adherence to the Mediterranean diet (MD) is linked to a lower risk of all-cause mortality, with a 5% reduction in death risk for each one-point increase in the Mediterranean diet score (MDS).

The findings were supported by a meta-analysis of seven prospective studies, indicating that following the MD can significantly enhance survival prospects for elderly individuals, making it a beneficial dietary choice for this age group.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Mediterranean diet and mortality in the elderly: a prospective cohort study and a meta-analysis. Bonaccio, M., Di Castelnuovo, A., Costanzo, S., et al.[2019]

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