Weight Loss

Longterm Studies Show Keto Diet Potentially Harmful to Body

Previously, we shared info on the popular Keto diet, the super low carb weight loss approach. Low carb diets are not new, popularized in the 1920s to treat epilepsy and diabetes, but the trend shifted to increasingly low amounts of carbs, morphing into the well-known Keto diet of today. The keto diet relies on ketone bodies, a type of fuel that the liver produces from stored fat when the body is in starvation mode, rather than the body relying on sugar that comes from carbohydrates. Keeping the body in ketosis can cause weight loss. However, new studies show that keto diets and other low-carbohydrate diets have been linked to increased mortality.

“We used to have these diets where people would just drink juice and water for three days and lose X amount of pounds,” said Dr. David Heber, MD, PhD, an internist and founding director of the UCLA Center for Human Nutrition, adding “That’s, in a way, a safety effect because if you quit after two weeks, you’re not going to hurt yourself.” He went on to explain, “If you’re on a keto diet for a week or two, you’ll live, but it may not be effective for you in the long term”.

In the 1920s, ketogenic diets were first used to treat diabetes. This was prior to the discovery of insulin. Limiting carbs to 5% of calories can be beneficial for those with pre-diabetes or type 2 diabetes, helping control blood glucose if it contributes to weight loss and weight management, says one source. However, while keto diets may improve blood glucose in the short term, “there is inconclusive scientific evidence that these diets are superior to other weight loss regimens in the long term.” While keto diets can be considered for controlling blood glucose in patients with prediabetes and type 2 diabetes, this approach must be monitored by a physician due to the potential negative outcomes related to maintaining a prolonged ketosis state.

Side effects common to people that decide to maintain a low carb diet must be monitored. For example, it is common to experience fatigue during exercise. People might also exhibit poor mental energy, increased hunger, sleep disturbance, muscle cramps, constipation, nausea and stomach discomfort. And that’s just the surface-level discomfort, (if you can call it that!). More serious complications include liver issues, kidney problems, increased gouty attacks, Osteoperosis, increased risk of heart disease, and more.

Studies show that over the long term, a diet in which only 5% of total calories come from carbohydrates makes it impossible to obtain optimum amounts of antioxidant phytonutrients from fruits and vegetables. Initial weight loss is likely due to significant urine production and fluid shifts. That change requires monitoring as it may require medication dosages to be adjusted, such as those for hypertension, heart failure, and diabetes.

Staying active is important

It is important that if a patient decides to follow a keto diet, that they exercise to build muscle and remain active. But, Dr. Heber explains, the body may needs some carbs. “There are a lot of diets out there that are what they call keto-friendly or keto-light,” which allows a person to have extra carbs to help offset exercise demands by keeping up glycogen stores. Consider increasing protein intake as well, to help provide the body the energy it needs. Both the increase in protein and a slight uptick in carbs will help ward off fatigue and get you through the workout.

While the research on weight loss benefits is exciting, there’s very little evidence to show that extreme low-carb eating is effective — or safe — over the long term for anything other than epilepsy. Plus, very low carbohydrate diets tend to have higher rates of side effects, including constipation, headaches, bad breath and more. My patients who tried keto diets had significantly abnormal labs and side effects. Yes, some saw significant weight loss. But everyone regained those pounds eventually.

Restricting carbohydrates also means limiting yourself from foods that support your body’s function, including fruits, veggies, grains, legumes, to name a few. A more promising approach? Try a whole foods diet, that limits processed foods, refined grains, and other unhealthy choices. Focus on foods proven to fight inflammation, support gut health, and help bolster your bodily function. Get adequate, regular sleep, and don’t forget the importance of hydration.

Please ask your provider about which foods will best help support your health.

Interested in learning more about Keto diets and the potential risks? Read our post, originally shared 7/19/2019, below.

What are Ketogenic Diets?

Many of my patients have been asking about a ketogenic diet. Is it safe? Would I recommend it? Despite the recent hype, a ketogenic diet is not something new. Russel Wilder first coined the phrase the “ketogenic diet” to treat epilepsy in 1921. For almost a decade, it enjoyed a place in the medical world as a therapeutic diet for pediatric epilepsy and was widely used until its popularity ceased with the introduction of anti epileptic agents.

In the 1970s, Dr. Atkins popularized his very-low-carbohydrate diet for weight loss that began with a strict two-week ketogenic phase. Over the years, other fad diets have incorporated a similar approach for weight loss. In the world of weight-loss diets, low-carbohydrate, high-protein eating plans often grab attention. The Paleo, South Beach, and Atkins diets fit into this category. They are all sometimes referred to as ketogenic or “keto” diets.

How do the diets work?

The keto diet aims to force your body into using a different type of fuel. Instead of relying on sugar (glucose) that comes from carbohydrates (such as grains, legumes, vegetables, and fruits), the keto diet relies on ketone bodies, a type of fuel that the liver produces from stored fat when the body is in starvation mode.

Burning fat seems like an ideal way to lose pounds. But getting the liver to make ketone bodies is tricky:

  • It requires that you deprive yourself of carbohydrates, fewer than 20 to 50 grams of carbs per day (keep in mind that a medium-sized banana has about 27 grams of carbs!).
  • It typically takes a few days to reach a state of ketosis.
  • Eating too much protein can interfere with ketosis.

What do you eat?

Carbohydrates normally account for at least 50% of the typical American diet. In the keto diet you’re limited to only 5-10%. Specifically, in a 2,000 Kcal per day diet, you’d only be allowed up to 20 to 50 grams per day.  A ketogenic diet primarily consists of high-fats, moderate-proteins, and very-low-carbohydrates. The rest of the dietary macronutrients are divided into approximately 55% to 60% fat and  30% to 35% protein.

Because the keto diet has such a high fat requirement, followers must eat fat at each meal. In a daily 2,000-calorie diet, that might look like 165 grams of fat, 40 grams of carbs, and 75 grams of protein. However, the exact ratio depends on your particular needs.

Some healthy unsaturated fats are allowed on the keto diet — like nuts (almonds, walnuts), seeds, avocados, tofu, and olive oil. Saturated fats from oils (palm, coconut), lard, butter, and cocoa butter are encouraged in high amounts.

Protein is part of the keto diet, but it doesn’t typically discriminate between lean protein foods and protein sources high in saturated fat such as beef, pork, and bacon.

What about fruits and vegetables? All fruits are rich in carbs, but you can have certain fruits (usually berries) in small portions. Vegetables (also rich in carbs) are restricted to leafy greens (such as kale, Swiss chard, spinach), cauliflower, broccoli, Brussels sprouts, asparagus, bell peppers, onions, garlic, mushrooms, cucumber, celery, and summer squashes. 

There are multiple risks to a keto diet.

Hard to metabolize: Meat is harder to break down in the digestive system than plants are. Eating a diet that is high in meats and natural fat may be taxing on the digestive system. Eating high fat meals all the time overloads the digestive system with hard to digest food, instead of plant-based sources. Plants such as fruits and vegetables also act as natural detoxification agents to eliminate toxins from the body.

Nutrient deficiency: If you’re not eating a wide variety of vegetables, fruits, and grains, you may be at risk for deficiencies in micronutrients, including selenium, magnesium, phosphorus, and vitamins B and C.

Liver problems: With so much fat to metabolize, the diet can cause or exacerbate any existing underlying liver conditions.

Kidney problems: The kidneys help metabolize protein, and the keto diet may overload them by recommending a third more than what’s encouraged. (The current recommended intake for protein averages 46 grams per day for women, and 56 grams for men).

Constipation: The keto diet is low in fibrous foods like grains and legumes so abdominal bloating and gas is common.

Fuzzy thinking and mood swings: The brain needs sugar from healthy carbohydrates to function. Low-carb diets may cause confusion and irritability. Eating high fat meals all the time can also make a person tired because plants such as fruits and vegetables provide natural energy. 

Osteoporosis: A condition that is characterized by loss of the normal density of bone, resulting in brittle bones, which are subject to fracture. The disease process can be silent (without symptoms) for decades. There is a potential increased risk of osteoporosis with a low-carb diet where calcium loss can result if protein intake remains high and calcium intake remains low. The ratio of animal to vegetable protein intake may also contribute to bone loss.

Increase gouty attacks: For now, it’s best to stick with conventional wisdom regarding food and gout — that most diets high in animal proteins are risky for a person with gout. We know that red meats and seafood are especially rich sources of purines, and when eaten in excess, can raise uric acid levels. When people with gout ate a diet high in purines from animal sources over a two-day period, they were nearly five times more likely to have a gout flare compared with people who avoided purines, in a study from Boston University published in the journal Annals of The Rheumatic Diseases. “A poor diet can absolutely lead to more gout exacerbations, even if the uric acid is fairly controlled with medication,” says rheumatologist Randall N. Beyl Jr, MD.

Increased risk of heart disease: Research shows there is an association between eating a diet high in animal products and heart disease. Many animal products are high in saturated fats that are high in cholesterol, which can clog arteries and impact blood flow to the heart. Blood delivers important nutrients and oxygen needed to maintain proper cardiovascular system health. The ketogenic diet is both high in saturated animal fats and low in protective antioxidants from plant sources, as antioxidants protect organs such as the heart, further increasing an individual’s risk of developing this disease. It’s recommended that saturated fats be limited to no more than 7% of your daily calories because of the link to heart disease. The keto diet is associated with an increase in “bad” LDL cholesterol, which is also linked to heart disease. I have seen significant changes in lipid control on these diets, often elevating lab values to dangerous levels that can cause significant harm in the long run.

Diabetes: Fiber is only found in plant sources of food and is limited while on the ketogenic diet. Fiber controls blood sugar levels by limiting the amount of glucose that is dumped into the bloodstream. Because of this, fiber reduces blood sugar spikes and can help control diabetes. Eating a diet that is high in vegetables is the best way to incorporate fiber into one’s diet. This would be hard to accomplish on a diet that limits its overall carbohydrate intake to just two to four percent. Or as previously stated- the equivalent of a small banana.

Skin issues: Research indicates a link between eating meat and acne. The ketogenic diet is high in meat and low in vegetables, which have healing powers for the skin. Vitamins A, C, and E can help prevent the appearance of skin wrinkles. They can also protect the skin against the sun’s damaging UV rays. Vitamin C is necessary for collagen production, which helps restore new, healthy skin. These vitamins are only found in plant sources such as fruits and vegetables. A person with a diet that is high in meats and low in fruits and vegetables may experience more skin problems than a person who follows a plant-based diet.

Interact with medications: For example, there is some evidence the ketogenic can pose dangers for anyone with high blood pressure. Blood pressure medications and this diet method can react adversely to one another due to a sudden drop in blood pressure in the first few weeks. Considering the ketogenic diet can be harmful to those with high blood pressure, consulting a medical professional is a critical step in avoiding or minimizing any concerns.

It’s expensive: If you and your family are on a tight budget, properly following and thriving on the ketogenic diet can be difficult. For one, with the rising cost of food, especially meats, and animal-based products, this diet can get expensive quick as a majority of your protein and fat sources come from animal-based proteins and fats. And many of the ketone supplements can get incredibly expensive as well, especially if there are more than two individuals in a household following the diet, as you will need to buy supplements more often. Unless you plan to start buying in bulk or purchasing meats and organic foods when they are on sale and freezing them, expect to see your grocery bill increase significantly on the ketogenic diet.

These risks add up- so make sure you talk to provider before ever attempting a ketogenic diet.

What about the other diets?

The popular low-carb diets (such as Atkins or Paleo) modify a true keto diet. But they come with the same risks if you overdo it on fats and proteins and lay off the carbs. So why do people follow the diets? They’re everywhere, and people hear anecdotally that they work, so they want to try them too. It also sounds like a quick fix to a long term issue. While in the short term the ketogenic diet may help one lose weight, this is not sustained over the long run. In addition, countless studies show that the diet is associated with many complications that often lead to emergency room visits and admissions for dehydration, electrolyte disturbances, and hypoglycemia (low blood sugar level.) 








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