The ketogenic or “keto” diet, a low-carbohydrate, fat-rich eating plan, has gained considerable attention as a potential weight-loss strategy. It has been used for centuries to treat specific medical conditions. In the 19th century, it was commonly used to help control diabetes, and in 1920, it was introduced as an effective treatment for epilepsy in children in whom medication was ineffective. This article delves into whether you can eat more calories on a keto diet while still achieving your weight loss goals.
Understanding the Ketogenic Diet
The premise of the ketogenic diet for weight loss is that if you deprive the body of glucose-the main source of energy for all cells in the body, which is obtained by eating carbohydrate foods-an alternative fuel called ketones is produced from stored fat. The brain demands the most glucose in a steady supply, about 120 grams daily, because it cannot store glucose. During fasting, or when very little carbohydrate is eaten, the body first pulls stored glucose from the liver and temporarily breaks down muscle to release glucose. If this continues for 3-4 days and stored glucose is fully depleted, blood levels of a hormone called insulin decrease, and the body begins to use fat as its primary fuel. The liver produces ketone bodies from fat, which can be used in the absence of glucose. When ketone bodies accumulate in the blood, this is called ketosis. Healthy individuals naturally experience mild ketosis during periods of fasting (e.g., sleeping overnight) and very strenuous exercise.
There is not one “standard” ketogenic diet with a specific ratio of macronutrients (carbohydrates, protein, fat). The ketogenic diet typically reduces total carbohydrate intake to less than 50 grams a day-less than the amount found in a medium plain bagel-and can be as low as 20 grams a day. Generally, popular ketogenic resources suggest an average of 70-80% fat from total daily calories, 5-10% carbohydrate, and 10-20% protein. For a 2000-calorie diet, this translates to about 165 grams fat, 40 grams carbohydrate, and 75 grams protein. The protein amount on the ketogenic diet is kept moderate in comparison with other low-carb high-protein diets, because eating too much protein can prevent ketosis.
Many versions of ketogenic diets exist, but all ban carb-rich foods. Some of these foods may be obvious: starches from both refined and whole grains like breads, cereals, pasta, rice, and cookies; potatoes, corn, and other starchy vegetables; and fruit juices. Some that may not be so obvious are beans, legumes, and most fruits. Most ketogenic plans allow foods high in saturated fat, such as fatty cuts of meat, processed meats, lard, and butter, as well as sources of unsaturated fats, such as nuts, seeds, avocados, plant oils, and oily fish. Strong emphasis on fats at each meal and snack to meet the high-fat requirement. Some dairy foods may be allowed. Although dairy can be a significant source of fat, some are high in natural lactose sugar such as cream, ice cream, and full-fat milk so they are restricted. Protein stays moderate. Certain fruits in small portions like berries. Fruits other than from the allowed list, unless factored into designated carbohydrate restriction.
The Role of Calories in Weight Loss on Keto
To lose weight, a person needs to burn more calories than they consume. People who consume too many calories may gain weight, even if they are in a state of ketosis. It is, therefore, important that people keep track of the number of calories that they consume. Sticking to a balanced meal plan can help a person work toward their ideal weight.
Read also: Timeless Design by Dieter Rams
Calories are a measure of energy. When it comes to nutrition and health, the foods you eat provide you with calories so that you can survive. Foods vary in their number of calories depending on the macronutrients present. Dietary fat has the highest calorie density, providing 9 calories per gram. Besides giving your body the energy it needs for physical activities, calories on keto diet can be tracked if an individual fails to see the weight loss results they’ve been hoping for. But let’s say you’re just getting started on the keto diet.
The general consensus is that strict calorie counting on keto is unnecessary because ketosis, which results from eating very few carbohydrates, teaches your body to burn fat at a greater rate. What’s more, counting calories on keto is not suitable for everyone. According to an older study, calorie tracking has been perceived to contribute to an eating disorder. On the flip side, calorie counting may be useful in situations where you tend to eat too much fat on keto, which ultimately results in a weight loss stall. Another good reason to become aware of your calorie intake (even though you’re on a satiating diet plan) is that it can keep you accountable.
How many calories you eat in a day on the keto diet will depend on many variables. This includes your activity level, sleep quality, stress, intake of processed foods, and alcohol consumption. Activity level, for instance, can affect a person’s calorie needs and the number of calories they burn. Athletes and those who spend more time at the gym, in general, have higher caloric and macronutrient requirements to support their performance and recovery. Sleep quality, or how well you’re sleeping, also influences your calorie intake. You may be on a diet that supports weight loss, but keep in mind that insufficient sleep is associated with eating habits that increase your risk for weight gain. Being stressed out, especially long-term stress can lead to the consumption of hyper-palatable foods (those that are high in both fat and sugar) as a way of seeking comfort. With regard to alcohol intake, research suggests that alcohol consumption may be a significant risk factor for weight gain. Not just that, but drinking alcohol can increase your food cravings as well.
The Metabolic Advantage of Ketogenic Diets
When matched for calories, low-carbohydrate diets (higher fat and protein intake) have a “metabolic advantage” compared to low-fat high-carbohydrate diets. What this means is that for the same amount of calories, low-carb diets result in a greater amount of weight loss compared to high-carb diets. This is probably due to their thermodynamic effect. The studies showing superior weight loss on ketogenic compared to low-fat diets support this claim, as do trials that measure basal metabolic rate (BMR). Low-carb diets might increase energy expenditure by 100 - 500 calories per day.
The additional thermic effect of food means that an increased energy expenditure will result in more calories burned, and thus more weight loss in the long term. Better weight loss probably results from several factors. The first is the high thermic effect of protein. Protein takes more energy to metabolize compared to carbohydrates and fat. However, some keto advocates advise not consuming too much protein while on keto. Second, a process called gluconeogenesis (GNG) requires energy. When carbohydrate intake is low (and so are glucose and glycogen), the body uses amino acids (from protein breakdown) to create glucose that’s needed by certain body tissues and cells like red blood cells and certain parts of the eye. GNG is energetically costly-it’s estimated that around 400 - 600 extra calories per day may be required for GNG to occur (for instance, in someone on a ketogenic diet).
Read also: Sustainable Future with Vegetarianism
Keto adaptation also increases the rate of fat-burning compared to other diets. Low insulin levels trigger the breakdown of triacylglycerols (TAGs) in fat into free fatty acids. Low insulin also inhibits fat storage.
Appetite Suppression on Keto
One of the most touted, research-backed aspects of the ketogenic diet is appetite suppression, which some refer to as “satiation” (basically, the condition of “feeling full” and satisfied). A common "symptom" of ketogenic diets is that they seem to be superior to other diets in terms of regulating hunger. This is probably due to the macronutrient composition of keto diets-they’re high in fat and moderate in protein, which are claimed to be more satiating nutrients.
For most people beginning the ketogenic diet, counting calories isn’t necessary for the first 2-3 months. The body undergoes a period of metabolic adaptation during which it naturally reduces appetite and improves satiety signalling. This mechanism works through several biochemical pathways. Ketones directly affect the satiety centre in the hypothalamus, sending signals to reduce hunger. Appetite-regulating hormones also undergo beneficial changes. Ghrelin levels (hunger hormone) drop, whilst leptin (satiety hormone) begins working more effectively.
Factors Influencing Calorie Needs on Keto
Caloric requirements on the ketogenic diet depend on many factors, but the basic energy equation still applies - with significant modifications. Basal metabolic rate (BMR) can increase by 5-15% in the first weeks of ketosis thanks to increased thermogenesis. Physical activity also affects energy balance differently. In ketosis, the body more efficiently utilises its own fat reserves during exercise, which can effectively reduce the requirement for additional dietary calories.
Ketogenic caloric guidelines differ somewhat from traditional recommendations. Women need approximately 1,200-1,600 calories daily, whilst men require 1,500-2,000 calories - depending on physical activity participation throughout the day and individual body composition. Very active individuals may add 200-400 more calories to their menu. For effective weight loss, create a caloric deficit of approximately 20-25% relative to your total daily requirement. However, don’t go below 1,200 calories (women) or 1,500 calories (men) to avoid metabolic slowdown. In the weight maintenance phase, consume calories at your total daily energy expenditure (TDEE) level. Gradually increase intake by 100-150 calories weekly until achieving balance.
Read also: Optimal Health: Diet or Workout?
Women and Keto: Unique Considerations
Women have a unique hormonal profile that affects metabolism and energy requirements on the ketogenic diet. In the first phase of the menstrual cycle (follicular), when oestrogen levels rise, the body better utilises carbohydrates as fuel. In the luteal phase (after ovulation), when progesterone dominates, there’s a natural shift towards fat burning. Stress hormones also work differently in women. Cortisol can more drastically affect female metabolism, particularly during menopause. Muscle mass is on average lower in women, translating to lower basal metabolic rate. Simultaneously, women have a higher percentage of adipose tissue, which is less metabolically active.
Female metabolism on keto requires subtle adjustment. Active women (25-35 years) need 1,400-1,700 calories daily, whilst those with sedentary lifestyles require 1,200-1,400 calories. Post-menopausal women should limit themselves to 1,200-1,500 calories due to naturally slowed metabolism. Drastic caloric restriction can completely disrupt delicate hormonal balance. Consuming fewer than 1,200 calories daily can cause menstruation cessation, thyroid hormone reduction, and paradoxical weight loss slowdown. Insulin level stabilisation often leads to natural appetite reduction and better portion control. Women with PCOS (polycystic ovary syndrome) particularly benefit from improved insulin sensitivity. Stable ketone levels eliminate energy fluctuations that lead to uncontrolled hunger episodes. The result? Most women spontaneously reduce caloric intake without accompanying hunger feelings.
When Calorie Counting Becomes Useful
There are situations where counting calories becomes useful, even essential. Individuals with a long history of dieting, including experiences with recurring yo-yo effects, may have disrupted perception of hunger and satiety. Patients with insulin resistance may also need greater control over caloric intake, and those training require precise energy adjustment to their intended expenditure. Women during menopause may require greater control due to hormonal metabolic changes. Mobile phone applications offering dedicated functions for the keto diet are a good solution.
Optimising Caloric Intake on Keto
Optimising caloric intake on the ketogenic diet requires a holistic approach that considers not only calorie numbers but also timing, quality, and daily distribution. The metabolic flexibility achieved through ketosis allows greater freedom in energy management. One of the most effective approaches is cyclical calorie adjustment based on activity levels. On training days, intake can be increased by 200-300 calories, mainly from fats - to support recovery and protein synthesis. Intermittent fasting (IF) combines perfectly with the ketogenic diet, allowing natural eating window restriction. Concentrating caloric intake within a 6-8 hour window can further improve insulin sensitivity and accelerate weight loss. Calorie quality is of paramount importance. Calories from processed trans fats work differently than calories from natural saturated fats or omega-3s.
Too large a caloric deficit sends the body an alarm signal - “starvation, conserve energy!” Basal metabolic rate can drop, thyroid hormone levels drastically decrease, and leptin production collapses and slows. Paradoxically, the body may “halt” ketogenesis as a survival mechanism, despite adhering to carbohydrate limits. Chronic caloric excess can lead to weight gain, despite maintaining ketosis. The body in ketosis can “waste” some excess energy through thermogenesis - increased heat production, but this mechanism also has limitations.
Tips to Maintain a Healthy BMI on Keto
The following tips may help achieve and maintain a healthy BMI on the keto diet:
- Keeping a food journal: By keeping track of what they consume throughout the day, a person can often identify any foods or eating patterns - such as snacking - that may be preventing weight loss.
- Drinking plenty of water: Drinking plenty of water helps fill the stomach, and this may help keep a person from overeating or snacking too much throughout the day.
- Getting plenty of sleep: Sleep helps regulate the body’s normal cycles, and it may also help reduce stress levels.
- Planning meals: A person may benefit from adhering to a keto-friendly meal plan.
Addressing Potential Weight Loss Stalls on Keto
As you’ve learned, it is still possible to go over your calories and deal with excess weight along the way. Compared to fast food and takeouts, meals prepared at home are healthier because you have control over the ingredients. Broccoli, asparagus, cauliflower, salad greens, avocados, strawberries, and blueberries are examples of non-starchy fruits and veggies. Adding more of these options to the keto diet is a great way to control your calorie intake for two reasons. When done correctly, snacking is a great source of fuel and nutrients for the day. On the contrary, snacking can be done out of boredom or to experience relief from a stressful situation. While there are mixed opinions about snacking, the reality is that it can be both positive and unhelpful depending on your habits. Base your snacking frequency on your activity level. If you’re very active, have two snacks a day. Instead of high-sugar snacks, choose those that contain fiber and are high in protein. Protein, which is consumed in moderate amounts on the keto diet, can help increase the calories you burn. This is because of its thermic effect, which is higher than carbohydrates and fat. Note that adults need 7 or more hours of sleep.
There are various reasons why a person may not lose weight while following the keto diet. Usually, when a person does not lose weight on the keto diet, it is because they have not achieved ketosis. One reason for not achieving ketosis is not cutting back enough on carbs. According to a 2023 overview of previous research. carbohydrates should represent only 5-10% of a person’s calorie intake on the ketogenic diet. Specifically, most keto diets require a person to cut down to between 20 and 50 grams of carbs each day on a 2000-calorie-per-day diet. Sometimes, a person may feel as though they have drastically reduced their carb intake. However, they may still be eating enough carbs for the body to produce energy from glucose, and this may reduce the rate of fat burned in the body.
A person not losing weight on the keto diet may benefit from purchasing a home testing kit. These kits contain test strips that check for ketones in the urine. A positive result indicates that the body is in ketosis. Another option is to use a small machine called a ketone breath analyzer that detects ketones in the breath. People can use this information to make dietary changes to help them achieve their weight loss goals.
Some people mistakenly think a low carb, high protein diet is a keto diet. However, this type of diet is unlikely to cause ketosis because the body can break down excess proteins into amino acids and convert them to types of sugar. A person on the keto diet will get most of their calories from fat, which should represent about 55-60% of their calorie intake. This fat intake leaves little room for protein. If protein makes up more than 35% of a person’s diet, they may not go into ketosis.
On the keto diet, several types of carbohydrates are acceptable, including nuts and dairy. These foods are typically high fat, nutrient-dense foods that make a great addition to a keto diet. However, they also contain carbohydrates. Eating too many of these foods will keep a person from achieving and maintaining ketosis.
For example, although maltitol is technically a low glycemic index (GI) sugar, it can still affect a person’s blood sugar levels. Consuming too much maltitol may prevent a person from entering ketosis.
Many alcoholic drinks, such as wine or beer, are high in carbohydrates. Hard alcohols, such as gin and vodka, contain less sugars, meaning they are lower in carbohydrates. However, alcoholic drinks contain many calories. As such, even these options can prevent weight loss.
Exercise is an important part of staying healthy. Exercise also stimulates the body’s metabolism and burns calories. Exercise may be especially important on a keto diet, as the high fat foods a person eats contain many calories. Burning calories through exercise can help a person reach their desired weight.
A high-stress lifestyle can also stop a person from losing weight on the keto diet. Psychological stress can cause changes in hormone levels, such as cortisol, which can lead to weight gain or difficulty losing weight. Chronic stress may also cause people to crave comfort foods, which can add extra calories to the diet.
In some cases, an underlying medical condition can cause weight gain or prevent weight loss. Alternatively, a medication that a person takes for the underlying condition may be causing increased appetite as a side effect. Some conditions that can contribute to weight gain include some endocrine conditions, such as hypothyroidism, polycystic ovary syndrome, Cushing’s syndrome, mental health conditions, such as depression and chronic stress. A person should contact a doctor if they are unable to lose weight despite adhering to a strict diet and exercise plan. The doctor may carry out tests to determine what is preventing weight loss. Treating the underlying condition may resolve the issue.
Potential Risks of the Keto Diet
Following a very high-fat diet may be challenging to maintain. Some negative side effects of a long-term ketogenic diet have been suggested, including increased risk of kidney stones and osteoporosis, and increased blood levels of uric acid (a risk factor for gout). Possible nutrient deficiencies may arise if a variety of recommended foods on the ketogenic diet are not included. It is important to not solely focus on eating high-fat foods, but to include a daily variety of the allowed meats, fish, vegetables, fruits, nuts, and seeds to ensure adequate intakes of fiber, B vitamins, and minerals (iron, magnesium, zinc)-nutrients typically found in foods like whole grains that are restricted from the diet.
The high-fat nature of the diet could also have negative impacts on heart health. The American Heart Association recommends limiting saturated fat intake to less than 6%. In practice, many people eat high amounts of saturated fats, which could increase your risk of heart disease. You may be eating a lot of fatty meat thinking it’s a good thing for you because it's high in fat. This can dramatically alter your lipid profile. While high-fat diets can elevate LDL (“bad”) cholesterol, the type of saturated fat matters. The bottom line is that having more fats in your diet can lead to higher cholesterol. We know that higher cholesterol tends to increase your chances of heart attacks and strokes.
The keto diet may not be appropriate for everyone, specifically people with kidney disease. Although more research is needed in that area, there is some suggestion that it can make kidney disease worse over time. Some people also experience dehydration on the keto diet because they’re eliminating glycogen, which holds water, from the bloodstream. The keto diet can cause your blood pressure to drop in the short term due to a reduction in blood volume and changes in your fluid balance. Symptoms of low blood pressure include dizziness, lightheadedness or fainting, especially when standing up quickly. Following a keto diet can also cause your blood sugar to drop, which can be dangerous for people living with diabetes. Common symptoms of low blood sugar include weakness or shaking, sweating, a fast heartbeat and dizziness.
Alternatives to Strict Keto
Intermittent fasting is an approach that allows you to receive the benefits of ketosis while still eating a varied and balanced diet. By cycling between periods of eating and fasting, your body enters “mild ketosis” during the fasting phase. Unlike the keto diet, which requires strict food restrictions, intermittent fasting lets you enjoy a variety of nutrient-dense foods, such as fruits, vegetables, whole grains and legumes, during eating windows.