September 16th 2025
By Ari Parker
Learn whether a keto diet is safe for seniors over 65. Discover benefits, risks, and expert recommendations for older adults considering ketogenic eating.
By Ari Parker
Nutritional therapy can be an effective way to lose weight or manage a chronic health condition, like Type 2 diabetes. But what does research say about the safety and efficacy of a keto diet for seniors?
Evidence suggests that some seniors can safely try the keto diet. Some may even experience health benefits, such as better glucose control.
But there are also serious risks to consider, including an increased risk for heart disease, liver and kidney problems, and medication interference. This is why it is essential to work with your healthcare provider to weigh the possible benefits and risks of the diet to your individualized health.
In this article, we’ll explain what a keto diet is, its potential risks and benefits, and how to safely try the diet as a senior.
The keto diet is safe for some seniors, but medical supervision is key to ensure you don’t experience any adverse effects, like medication interference or kidney or liver problems.
Possible benefits of the keto diet for seniors include weight loss and better blood sugar management.
Seniors considering a keto diet should consult with a healthcare professional to ensure the diet is right for them and their health.
The keto diet, also called the ketogenic diet, was first introduced in the early 20th century as a therapy for treating epilepsy in children. After the advent of antiepileptic medications and due to the diet’s severe restrictions, this type of treatment largely fell out of therapeutic use.
Today, it's more commonly implemented in adults as a diet that is high in fats (55-60%), moderate in proteins (30-35%), and very low in carbohydrates (5-10%). The primary goal of a keto diet is to reach a state called ketosis, where the body uses fat as its predominant energy source instead of glucose.
Many people who follow a keto diet aim to limit their daily carbohydrate intake to just 20-50 grams of net carbohydrates a day.
Net carbohydrates represent the total grams of carbs consumed minus the total grams of fiber and sugar alcohol consumed. The calculation is based on the fact that most fiber and sugar alcohols aren’t absorbed by the body.
For reference, one medium-sized apple has about 25 grams of carbohydrates and around 4-5 grams of fiber, which corresponds to 20-21 grams of net carbs. A medium-sized banana provides around 27 grams of carbohydrates and 2-4 grams of fiber.
In recent years, the keto diet has risen in popularity as a strategy for weight loss. People may also use the diet to try to manage:
Insulin resistance
Blood glucose levels
Certain neurological disorders
Support cancer treatment
The keto diet can be safe for seniors, but it’s important to take your individual health needs into consideration. Working with your primary healthcare provider and a registered dietitian, if possible, can help you to safely monitor your health when trying the keto diet. They can advise you on the best food sources for a keto diet while preventing any nutritional deficiencies and medication interference.
Unfortunately, the keto diet does carry several risks for seniors, especially for people with pre-existing conditions.
Some of the most common concerns for implementing a keto diet as a senior include nutrient deficiencies, heart disease, liver and kidney problems, and medication interference.
Other possible long-term and short-term concerns include:
Temporary side effects:
Nausea
Vomiting
Headache
Fatigue
Dizziness
Insomnia
Difficulty in exercise tolerance
Constipation
Dehydration
Long-term adverse side effects:
Hepatic steatosis (fatty liver disease)
Hypoproteinemia (low protein levels in the blood)
High cholesterol
Kidney stones
Because of a severe restriction of carbohydrates in a keto diet, it can be challenging to include substantial amounts of otherwise healthy foods rich in carbohydrates, including a variety of healthy grains, vegetables, and fruits.
Not eating enough healthy carbohydrates can lead to deficiencies in several vitamins and minerals, such as selenium, magnesium, phosphorus, and vitamins B and C.
Although the exact numbers may vary based on the type of keto diet you’re on, as much as 90% of your daily calories may come from fat. Not all types of fats affect our health in the same way, but some research suggests that increased intake of saturated fat may increase “bad” cholesterol (LDL) levels and therefore increase your risk for heart disease. Unfortunately, a keto diet encourages consumption of meats and animal fats that are high in saturated fat.
Because the keto diet is very high in fats, it can impact how the body absorbs and interacts with certain medications. According to one scientific review from 2024, following a keto diet can interfere with certain anti-diabetic, anti-epileptic, and cardiovascular drugs.
If you're on any type of medication, it’s important to work with your healthcare provider when implementing a keto diet to ensure that your medication continues to be effective and you don’t experience any adverse reactions or effects.
Evidence shows that following a high-fat diet like the keto diet can cause kidney and liver problems in some people.
Specifically, the keto diet can exacerbate symptoms in people with existing liver or kidney conditions. It can also increase the risk of developing kidney stones as a consequence of dehydration, especially in the initial stages when the body is still adapting to the diet change.
Though there are important risks to consider, research also indicates potential benefits to trying the keto diet as a senior.
One observational study evaluating the therapeutic outcomes of the keto diet in over 200 people aged 65 or older reported the following benefits:
Roughly 67% of patients accomplished their intended goal.
79% of patients who sought weight loss succeeded in losing weight.
57% of diabetes patients achieved better blood sugar control.
63% of patients successfully used the keto diet to support their cancer treatment and halt the growth of cancer cells.
However, studies on the outcomes of a keto diet for seniors are limited in scope and time. Existing research is not conclusive on the long-term sustainability of the keto diet, which is why any dietary changes must only be made in consultation with your healthcare provider.
Safely implementing the keto diet into your routine requires the collaboration of at least one healthcare provider. Working with your primary healthcare provider and/or a registered dietitian ensures that you’re able to monitor your health and any possible adverse reactions when trying the keto diet.
If you are currently on medications, such as insulin, your healthcare provider might modify your dosage to support your health outcomes. For people with pre-existing conditions, such as heart disease, your doctor may recommend alternative food sources with lower levels of saturated fats so you can stay on the diet.
Research shows that some seniors may benefit from a keto diet. Potential benefits include weight loss and better glucose management.
But there are also serious risks to consider, especially as a senior. Before trying the keto diet, it’s crucial to consult with your healthcare provider to ensure that the diet is safe for you and won’t interfere with any medications you’re currently taking. Your provider can also work with you to monitor your health while making any dietary or nutritional changes.
Yes, some seniors can safely try a keto diet. But the diet does carry risks, including nutritional deficiencies and kidney and liver problems, which is why it’s important to consult with your healthcare provider before switching to the keto diet as a senior.
What are the biggest risks of keto for older adults?
The biggest risks of trying the keto diet as an older adult include nutritional deficiencies, increased risk of heart disease, medication interference, and kidney and liver problems, which may be exacerbated by pre-existing conditions.
Some seniors with diabetes may benefit from a keto diet and experience better blood sugar management while on the diet. But it’s important to work with a healthcare provider when trying the keto diet to ensure you don’t experience any adverse effects, especially if you’re on insulin or other diabetes medications.
Masood, W., Annamaraju, P., Mahammed, Z., Suheb, K., & Uppaluri, K. R. (2023). Ketogenic Diet. StatPearls. https://www.ncbi.nlm.nih.gov/books/NBK499830/
Should you try the keto diet? Harvard Health Publishing. (2024, March 28). https://www.health.harvard.edu/staying-healthy/should-you-try-the-keto-diet
Marinescu, S., Apetroaei, M-M., Nedea, M., Arsene, A. L., Velescu, B. S., Hîncu., Stancu, E., Pop, A. L., Draganescu, D, & Udeanu, D. I. (2024, April 19). Dietary Influence on Drug Efficacy: A Comprehensive Review of Ketogenic Diet-Pharmacotherapy Interactions. Nutrients. https://pubmed.ncbi.nlm.nih.gov/38674903/
Almodallal, Y., Cook, K., Lammert, L. M., Lee, M., Le-Rademacher, J. G., & Jatoi, A. (Nov 24, 2021). Can older patients adopt and maintain a ketogenic diet? An observational study in support of clinical trials in older patients. Medicine (Baltimore). https://pmc.ncbi.nlm.nih.gov/articles/PMC8615410/
