Keto Diet: Metabolism Booster Or Myth?

The keto diet is a popular weight-loss strategy that has gained traction over the years, with many people swearing by its effectiveness. The diet involves a significant reduction in carbohydrate intake, with the body then burning fat for energy instead of glucose. This state is known as ketosis, and it has been touted as a way to boost metabolism and promote weight loss. However, there are conflicting opinions on whether keto meals actually cause an increase in metabolism. While some sources claim that ketosis can lead to a faster metabolism, others argue that the keto diet may not be sustainable and could even lead to negative health outcomes.

Ketogenic diets can be bad for long-term heart health

The ketogenic (keto) diet has been gaining popularity as a weight-loss solution, but there are concerns about its impact on long-term heart health. While it can lead to short-term weight loss and improved overall health, there are risks associated with following a keto diet for extended periods.

The keto diet is a very low-carbohydrate, moderate-to-high protein, and high-fat diet. Typically, it consists of 60-80% fat, 20-30% protein, and only 10% carbohydrates. This means cutting out almost all sources of carbohydrates, including fruits, starchy vegetables, grains, beans, legumes, sugar, and alcohol. Instead, the diet relies on fat sources such as nuts, oils, butter, cream, and cheese to provide a feeling of fullness.

Impact on Heart Health

The keto diet's restriction of carbohydrates puts the body into a state of ketosis, where it burns fat for energy instead of glucose. While this can lead to weight loss and improved insulin sensitivity, there are potential negative consequences for heart health.

Previous research has shown that a low-carb, high-fat (LCHF) keto-like diet can lead to elevated levels of LDL ("bad") cholesterol. High levels of LDL cholesterol are associated with atherosclerosis, a build-up of plaque in the coronary arteries, which is a known risk factor for heart disease.

A recent study found that individuals following an LCHF keto-like diet over a nearly 12-year period had significantly higher levels of LDL cholesterol and twice the rate of experiencing major cardiovascular events, including heart attacks, strokes, peripheral artery disease, and clogged heart arteries requiring stent surgery.

Who Should Avoid the Keto Diet?

Dr. Brian Forrestal, an Atlantic Health System cardiologist, cautions that the keto diet is not suitable for everyone. He advises that individuals with heart disease, high cholesterol, a history of heart events or surgery, an eating disorder, or pregnancy should avoid the keto diet.

Alternative Heart-Healthy Diet Options

For individuals seeking to improve their heart health, Dr. Forrestal suggests a better-balanced, Mediterranean-style diet. This diet focuses on fresh vegetables, low-glycemic fruit, lean fish, white meat, whole grains, and a moderate amount of fat from sources like nuts and olive oil. Limiting sugar, salt, alcohol, red meat, and processed foods is also recommended.

While the research does not prove that the keto diet directly causes heart disease, it does show a strong correlation between following a ketogenic or keto-like diet and developing heart disease. Therefore, it is essential to consult with a healthcare professional before starting any new diet, especially if there are underlying health conditions or nutritional concerns.

Ketogenic diets are not sustainable for lifelong weight loss

• Sustainability: One of the biggest challenges with keto diets is their sustainability. People may be thrilled with the initial weight loss, but over time, they may get bored with the diet, feel weak and frustrated, and eventually increase their carbohydrate intake, leading to weight gain.
• Micronutrient deficiency: Ketogenic diets restrict fruits, vegetables, and grains, which are essential sources of micronutrients like selenium, magnesium, phosphorus, and vitamins B and C. This restriction can put individuals at risk for micronutrient deficiencies.
• Health concerns: The high saturated fat content of ketogenic diets is associated with an increase in "bad" LDL cholesterol, which is linked to heart disease. Additionally, these diets may overload the kidneys, as they play a crucial role in metabolizing the high amounts of protein consumed. There are also reports of liver problems, constipation, fuzzy thinking, and mood swings associated with keto diets.
• Yo-yo effect: "Yo-yo diets," like the keto diet, that lead to rapid weight loss fluctuation, are associated with increased mortality. Once an individual resumes a normal diet, they are likely to regain the weight lost.
• Inflammatory pathways: Long-term low-carbohydrate diets with increased fat consumption have been hypothesized to stimulate inflammatory pathways, oxidative stress, and promote biological ageing.
• Hepatic insulin resistance: Recent studies suggest that ketogenic diets may induce hepatic insulin resistance, which can have negative implications for health.
• Cardiovascular safety: There are concerns about the cardiovascular safety of ketogenic diets due to their high saturated fat content and potential impact on cholesterol levels.
• Lack of long-term research: There is a lack of long-term research on the effects of ketogenic diets, possibly because people find them challenging to maintain for extended periods.

In conclusion, while ketogenic diets may show dramatic short-term improvements, they may increase morbidity and mortality in the long run and are rarely sustainable. A more balanced and less restrictive approach to diet and nutrition is generally recommended for long-term health and weight management.

Ketogenic diets can cause nutrient deficiencies

The keto diet may be lower in fibre because whole grains are eliminated, so you may experience constipation. A high-fat diet can also increase the risk of ketoacidosis for those with type-2 diabetes, and it may increase bad cholesterol.

A high-fat/low-carb diet like keto could lack the following vitamins and minerals: vitamin B1, vitamin B6, vitamin B7, vitamin B12, calcium, iron, magnesium, and phosphorus. These are all essential nutrients that the body needs to function properly.

B vitamins are necessary for turning food into energy. Calcium, magnesium, and phosphorus are crucial for strong bones. Iron is needed to carry oxygen and help the body grow and develop properly.

To avoid nutrient deficiencies on a keto diet, you can include high-quality meats like grass-fed beef, pastured pork, poultry, and eggs, which will provide the necessary B vitamins, iron, and phosphorus. Dark, leafy greens, broccoli, and avocados are good sources of vitamin B2, B6, B7, calcium, and magnesium. Full-fat yogurt is a good way to get vitamin B1, calcium, and phosphorus, while salmon, canned sardines, and some plant-based milks are good sources of calcium.

It is important to be aware of any nutrient deficiencies you may already have before starting a keto diet, as eliminating certain foods can exacerbate these deficiencies and cause additional health concerns.

Ketogenic diets can lead to a higher risk of heart disease

The ketogenic diet, which involves consuming low amounts of carbohydrates and high amounts of fats, has been linked to a higher risk of heart disease. While the diet may help with weight loss, there is scarce evidence for any long-term benefit.

Increased Risk of Heart Disease

The ketogenic diet has been associated with higher levels of "bad" cholesterol, or LDL cholesterol, and a higher risk of cardiovascular events such as chest pain, blocked arteries requiring stenting, heart attacks, and strokes. The diet's extreme carbohydrate restrictions may lead people to shun most vegetables and fruits, which can interfere with certain medications.

Short-Term Benefits

The ketogenic diet may lower blood levels of triglycerides and blood sugar and blood pressure, but these observed short-term benefits fade over time.

Individual Differences

Not everyone responds to the ketogenic diet in the same way. While cholesterol levels tend to rise on this diet, some people's cholesterol concentrations can stay the same or go down, depending on several underlying factors.

Limitations and Further Research

The available research is mostly observational, so it can only show an association between the diet and an increased risk of heart disease, not a causal relationship. However, the findings merit further research, especially given the popularity of low-carb diets.

Ketogenic diets can be bad for bone health

While the ketogenic diet has been touted for its weight loss and health benefits, there is growing evidence that it can have negative effects on bone health, particularly in athletes.

A study published in Frontiers in Endocrinology found that a ketogenic diet may "alter bone health in athletes" such as runners, who are prone to stress fractures and joint injuries. The study tracked male and female race walkers over several weeks of intense training and found that those who followed a keto diet developed "early signs indicative of bone loss." The data showed a decrease in bone density, which can have major consequences for health and performance.

The ketogenic diet involves keeping carbohydrate intake to a minimum, which can be challenging to maintain and may not be sustainable for many people. This strict restriction of carbohydrates can lead to a diet high in fat and protein, often from animal sources that are high in saturated fat. As a result, the keto diet has been linked to an increased risk of high cholesterol, clogged arteries, and heart disease.

In addition to the potential negative impact on bone health, the keto diet has also been associated with other health risks. These include low blood pressure, kidney stones, constipation, nutrient deficiencies, and social isolation or disordered eating. For these reasons, the keto diet is not recommended for those with conditions involving the pancreas, liver, thyroid, or gallbladder.

Furthermore, the keto diet may not be effective for long-term weight loss. While initial weight loss may occur, it is often followed by a weight rebound, where people regain the weight and may even gain back more. This is because the keto diet is often difficult to maintain, and people tend to return to a normal diet, which includes carbohydrates. As a result, the body becomes less tolerant of carbs, leading to a negative impact on metabolism and potential weight gain.

Therefore, while the ketogenic diet may offer some benefits, it is important to consider the potential risks, particularly the negative impact on bone health and the long-term sustainability of the diet.

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