Weight loss is a goal for many, and understanding the role of calories is crucial in achieving it. This article provides a detailed overview of how to use a calorie scale for weight loss, covering everything from basic energy needs to advanced strategies like zigzag calorie cycling.
Understanding Basal Metabolic Rate (BMR)
We all need a basic amount of energy for our bodies to function, commonly called basal metabolic rate. Your body requires this amount of energy each day even if you’re resting comfortably in a bed the whole day, awake but not moving other than breathing. These functions provide energy to cells and tissues, circulate blood, assist with breathing, and support all your organs, like the lungs, brain, digestive tract, and kidneys.
Factors Influencing Calorie Needs
Other factors, on top of the basal metabolic rate, can influence your calorie needs. According to the Dietary Guidelines for Americans, daily calorie needs vary based on many factors, including age, sex, height, weight, physical activity level, and pregnancy or lactation status.
Maintaining, Losing, or Gaining Weight
To maintain your weight, you need to consume about the amount of daily calories that your body requires to support your basal metabolic needs and all your regular physical activity. To lose weight, you need to eat fewer calories than your body requires at your current activity level.
Calculating Your Estimated Daily Energy Needs
To determine the number of calories you need to maintain or lose weight, start by weighing yourself to find your current weight. If your weight is already in a healthy range for your height, you should aim to eat the number of calories required to maintain your weight. Healthy weight can be a subjective term, but the American Cancer Society provides a chart on healthy weights and the Centers for Disease Control and Prevention (CDC) provides guidance on calculating your body mass index (BMI).
Read also: Diet Before Bariatric Surgery
Goal Weight and Timeframe
If you’d like to lose weight, use a weight loss calculator to generate estimated calorie needs for gradual weight loss at your current weight. Choose a realistic goal weight, or try a few different goal weights to see what the calculator will suggest for your calorie needs. Most weight loss calculators will use your goal weight to generate a calorie amount that should lead to gradual weight loss. Weight loss calculators often ask your desired goal date for your desired weight to help determine your calorie goal. If you wish to lose weight faster, the calculators give a lower daily calorie goal. If you have more time for weight loss, the daily calorie goal may be higher.
Important Considerations for Calorie Goals
Note that all weight loss calculators have limitations, and they may give you an unsustainably low calorie goal if you enter a large amount of weight to lose with a short goal date. Although this number varies depending on body size and activity level, as an RD I recommend no fewer than 1,200 to 1,300 calories per day for women and 1,400 to 1,500 calories per day for men to cover basic metabolic needs.
The Impact of Biological Sex and Age
Biological sex affects calorie needs because of varying muscle mass and body size. Biological men tend to have larger body frames than women, with more muscle mass. Larger body sizes and more muscle mass increase calorie needs. Calorie needs are generally higher when we’re younger and decrease over time as we age. This decrease in calorie needs results from reduced physical activity, loss of muscle mass, gains in fat mass, and lower basic metabolic needs as we age. A woman who is 35 and active has higher calorie needs than a woman who is 65 with the same activity level.
Height and Activity Level
A taller person generally has more body mass than a shorter person. Bodies with more mass need more energy to carry out essential life functions, and they use more energy during physical activity, too. Your level of physical activity affects your daily calorie needs. Use this calorie calculator to help you achieve and maintain your weight loss or weight gain goals within a realistic timeframe. It calculates the daily calorie intake and the necessary macronutrients needed to reach your desired weight by your target date. Enter your age, sex, height, current, and goal weight. Click the Physical Activity field to find your physical activity level. Physical activity levels can range from 1.4 (little activity) to 2.3 (very active). The default is 1.4. If you are unsure of your physical activity level, start with the default - the worst-case scenario. Enter a time frame for your goal weight (start date and target date). Note that this tool is intended for individuals who are 18 years or older and are not pregnant or breastfeeding.
Minimum Calorie Intake
This weight loss calculator provides results only if it determines that your daily food energy intake needs to exceed 1,000 calories to reach your goal weight by your target date. Suppose it calculates that you need fewer than 1,000 calories. In that case, it will adjust your target date to ensure you consume at least 1,200 calories per day for women and 1,500 calories for men. Nutrition therapists recommend not going below these levels, as doing so can prevent you from meeting essential food group and nutrient requirements. You can adjust your target date later if you wish to modify your required calorie intake. If you plan to consume fewer than 1,000 calories (or 4,200 kJ) daily, please consult a doctor for guidance and support.
Read also: Complete Guide to 1500 Calorie Vegan Meals
Body Dynamics of Weight Change
Your body needs energy to stay alive and do physical activities. The primary energy source comes from glucose, which is blood sugar from the food you eat. When your body has more glucose than it needs for energy, it sends the extra to the liver and muscles to be stored as glycogen for later use. However, there is a limit to how much glycogen the liver and muscles can hold. Once they are full, any leftover glucose is turned into triglycerides and stored in fat cells. To lose weight, you must eat fewer calories than your body uses daily. This creates an energy deficit. When that happens, your body takes energy from its stores to meet its daily needs. This process leads to weight loss by breaking down fat and lean body mass.
Debunking the 3,500 Calorie Myth
A commonly held but incorrect belief about weight loss suggests that to lose 1 pound a week, you need to eat 500 fewer calories daily, which adds up to 3,500 calories fewer in a week. This idea comes from the assumption that fat tissue contains about 3,500 calories per pound, so by burning that many calories, you would lose 1 pound. However, the body doesn't operate in such a simple way. Eating 3,500 fewer calories doesn't mean your body will automatically burn 3,500 calories of fat. The reality is that when you lose weight, you lose fat along with some lean tissue in muscle - not just fat. Lean mass consists of everything that's not fat, including muscle, bones, organs, ligaments, tendons, other tissues, and water. The rule also ignores other body dynamics of weight loss, such as the reduction in basal metabolic rate (BMR) and decreased energy cost of physical activity. Your total daily energy expenditure (TDEE) changes with weight loss. Consequently, followers of diet programs based on this simple rule of thumb usually fail to reach their weight loss goal in the long run.
Accurate Calculation Models
This calculator uses the mathematical body model equations developed by Kevin Dennis Hall, Ph. D., and his team of researchers at the National Institute of Diabetes and Digestive Kidney Diseases of the National Institute of Health. It has been shown that his mathematical model can accurately determine an individual's energy requirements for weight management. It challenges the popular 3,500 calories per pound rule by accounting for the body dynamics discussed earlier, including body adaptations that oppose weight change and the weight change associated with changes to glycogen and extracellular fluid levels.
Macronutrient Balance
The calculator will calculate your macronutrient requirements (carbs, protein, and fat) in grams based on the required caloric intake to reach your goal weight with a balanced, low-fat, low-carb, and high-protein diet. According to the Food and Nutrition Board of the Institutes of Medicine (IOM) dietary guidelines, an acceptable macronutrient distribution range is 45%-65% of calories for carbohydrates, 10%-35% for protein, and 20%-35% for fat. The calculated amounts put each macro's percentage within the IOM acceptable range for the different diet types. Knowing your macronutrient needs is important for planning meals and controlling portions. If you want to lose weight, gain weight, or keep your weight steady, understanding how many calories you need and the right balance of macronutrients can help you make better food choices and reach your goals.
Calorie Counting: A Practical Approach
There are many approaches to weight loss and there is no set ideal method that works for all people, which is why so many different diets and exercise regimens exist. While some methods are more effective for each individual person, not all weight loss methods are equivalent, and studies suggest that some approaches are healthier than others. That being said, one of the most commonly effective weight loss methods is counting calories. In its most basic form, calories consumed minus calories expended will result in weight gain if the result is positive, or weight loss if the result is negative. However, this is far from a comprehensive picture, and many other factors play a role in affecting healthy, sustainable weight loss. For example, there exist conflicting studies addressing whether or not the type of calories or foods consumed, or how they are consumed, affects weight loss. Studies have shown that foods that require a person to chew more and are more difficult to digest result in the body burning more calories, sometimes referred to as the thermic effect of food.
Read also: Healthy Vegetarian Eating
Advantages of Calorie Counting
Aside from being one viable method for facilitating weight loss, calorie counting has other somewhat less quantifiable advantages including helping to increase nutritional awareness. Many people are completely unaware of, or grossly underestimate their daily caloric intake. Counting calories can help raise awareness of different types of foods, the number of calories they contain, and how these calories have a different effect on a person's feelings of satiety. Having actual caloric measurements can also assist in weight loss, since tangible calorie goals can be set, rather than simply trying to eat less. Also, although this is not necessarily directly related to calorie counting, studies have shown that portion control by simply eating from a smaller plate can help reduce calorie intake, since people tend to fill their plates and eat everything on their plates. Many people do not realize that they are overeating, since they have become accustomed to restaurant-sized portions being the norm, when said portions can be up to three or more times larger than necessary for a typical meal. Tracking calories also puts exercise in a quantifiable perspective, increasing a person's awareness regarding how much exercise is really required to counteract a 220-calorie bag of M&M's. Once a link is made between the amount of exercise that some snack equates to, many people find abstaining from that bag of chips to be the preferred option rather than performing an equivalent amount of exercise - which can lead to healthier eating habits.
Choosing a Sustainable Strategy
In the end, however, what's important is picking a strategy that works for you. Calorie counting is only one method used to achieve weight loss amongst many, and even within this method, there are many possible approaches a person can take. Finding an approach that fits within your lifestyle that you think you would be able to adhere to is likely going to provide the most sustainable option and desirable result.
Zigzag Calorie Cycling
Zigzag calorie cycling is a weight loss approach that aims to counteract the human body's natural adaptive tendencies. Counting and restricting calories, as described above, is a viable method to lose weight, but over a period of time, it is possible for the body to adapt to the lower number of calories consumed. In cases where this happens, a plateau in weight loss that can be difficult to surmount can result. Zigzag calorie cycling involves alternating the number of calories consumed on a given day. A person on a zigzag diet should have a combination of high-calorie and low-calorie days to meet the same overall weekly calorie target. For example, if your target calorie intake is 14,000 calories per week, you could consume 2,300 calories three days a week, and 1,775 the other four days of the week, or you could consume 2,000 calories each day. In both cases, 14,000 calories would be consumed over the week, but the body wouldn't adapt and compensate for a 2,000-calorie diet. This also allows a person more flexibility in their diet, allowing them to plan around occasions, such as work or family gatherings, where a person may consume more calories.
Implementing Zigzag Cycling
There is no concrete rule or study that dictates the most effective way to alternate or spread out calorie consumption. How to vary calorie intake is largely up to personal discretion. Depending on a person's activity, it is generally recommended that the high-calorie and low-calorie days vary by approximately 200-300 calories, where the high-calorie day is often the number of calories a person needs to consume to maintain their current weight. For a person with a higher activity level, the calorie difference should be larger. The calculator presents two zigzag diet schedules. The first schedule has two higher calorie days and five lower calorie days. The second schedule increases and reduces calories gradually.
Finding the Right Method
In the end, regardless of what method you choose to use when approaching weight loss, what's important is picking a strategy that works for you. Calorie counting and zigzag calorie cycling are only two methods (that are fairly interrelated) used to achieve weight loss among many, and even within these methods, there are many possible approaches a person can take.
Determining Your Daily Calorie Needs
Many people seek to lose weight, and often the easiest way to do this is to consume fewer calories each day. But how many calories does the body actually need in order to be healthy? This largely depends on the amount of physical activity a person performs each day, and regardless of this, is different for all people - there are many different factors involved, not all of which are well-understood or known. Some factors that influence the number of calories a person needs to remain healthy include age, weight, height, sex, levels of physical activity, and overall general health. For example, a physically active 25-year-old male that is 6 feet in height requires considerably higher calorie intake than a 5-foot-tall, sedentary 70-year-old woman. The body does not require many calories to simply survive. However, consuming too few calories results in the body functioning poorly, since it will only use calories for functions essential to survival, and ignore those necessary for general health and well-being. Harvard Health Publications suggests women get at least 1,200 calories and men get at least 1,500 calories a day unless supervised by doctors.
Sources and Quality of Calories
The main sources of calories in a typical person's diet are carbohydrates, proteins, and fat, with alcohol also being a significant portion of calorie intake for many people (though ideally this should be limited since alcohol contains many empty calories). Some studies have shown that the calories displayed on nutrition labels and the calories actually consumed and retained can vary significantly. This hints at the complex nature of calories and nutrition and is why many conflicting points of view on the "best" methodology for losing weight exist. For example, how a person chews their food has been shown to affect weight loss to some degree; generally speaking, chewing food more increases the number of calories that the body burns during digestion. People that chew more also tend to eat less, since the longer period of time necessary to chew their food allows more time to reach a state of satiety, which results in eating less. However, the effects of how food is chewed and digestion of different foods are not completely understood and it is possible that other factors exist, and thus this information should be taken with a grain of salt (in moderation if weight loss is the goal). Generally, foods that take more effort to chew - fruit, vegetables, lean meats, whole grains, etc. - require the body to burn more calories since more calories are required to digest them. It also results in the feeling of satiety for longer periods of time. The "quality" of calories consumed is also important. There are different classifications of foods in terms of calories. This includes high-calorie foods, low-calorie foods, and empty calories. Consistent with their naming, high-calorie foods are foods that are calorically dense, meaning that there are a high number of calories relative to serving size, while low-calorie foods have fewer calories relative to serving size. Foods such as fat, oils, fried foods, and sugary foods are examples of high-calorie foods. Being a high-calorie food does not inherently mean that the food is unhealthy however - avocados, quinoa, nuts, and whole grains are all high-calorie foods that are considered healthful in moderation. Low-calorie foods include vegetables and certain fruits, among other things, while empty calories, such as those in added sugars and solid fats, are calories that contain few to no nutrients.
Practical Tips for Calorie Counting
Counting calories can help if you want to lose weight. You can begin by planning your weekly meals and counting calories per serving. However, it’s important to make sure you’re still fulfilling your daily energy needs. To lose weight, you typically need to eat fewer calories than you burn. Keep in mind that counting calories is just one way to lose weight. It may not work for everyone, and it’s not the only way to maintain a healthy diet and lifestyle. Always consider your food quality, portions, and fullness signals as well when trying to lose weight. You can speak with a healthcare professional, such as a dietitian, to help identify your individual food needs and goals.
Understanding Calories
Calories are a measure of energy, typically used to measure the energy content of foods and beverages. Your body uses the calories you eat and drink for essential functions, such as breathing and thinking, as well as day-to-day activities, such as:
- walking
- talking
- sleeping
- eating
Any excess calories you eat are stored as fat, so consistently eating more than you burn may lead to weight gain over time. How many calories you need depends on several factors, including:
- gender
- age
- weight
- activity level
If you’re trying to lose weight, you will typically need to create a calorie deficit by eating less than your body burns off. You can use this calculator to determine how many calories you should eat per day.
Additional Dietary Recommendations
When it comes to your weight, calories do count. This fact has been proven time and time again in scientific experiments called overfeeding studies. These studies ask people to deliberately overeat and subsequently measure the effect on their weight and health. All overfeeding studies have found that when people eat more calories than they burn off, they gain weight. A 2022 study split participants into two groups: those who tracked their calories and those who self-monitored high calorie foods. Both groups lost significant amounts of weight at the 6-month mark (5.7% and 4% on average, respectively). Thus, if it’s not possible to count all of your calories, you may be able to focus on high calorie foods and still lose weight.
Comprehensive Weight Loss Strategies
However, calorie counting isn’t the only effective method for weight loss. It’s also important to:
- incorporate whole foods into your diet
- exercise regularly
- maintain good sleep hygiene
Portion Control
Portion sizes have increased over time. In some restaurants, a single meal can provide double or triple the average person’s daily needs. “Portion distortion” is the term for when you view large servings of foods as the norm. It can cause weight gain and hinder weight loss. It can be tricky to estimate how much you eat each day. Calorie counting can help you manage overeating by giving you a better understanding of how much you are consuming.
Measuring Portion Sizes
For it to work, you need to record food portions correctly. Here are a few common ways to measure portion sizes:
- Scales: Weighing your food is the most accurate way to determine how much you’re eating.
- Measuring cups: Standard volume measures may be slightly quicker and easier to use than a scale.
- Comparisons: Comparing common items is quick and easy, especially if you’re away from home. However, this can be much less accurate.
Common Examples of Serving Sizes
Here are some common serving sizes compared with household items that may help you estimate your portion sizes:
- 1 serving of leafy green vegetables (1 cup): a baseball
- 1 serving of rice or pasta (1/2 cup): a computer mouse or rounded handful
- 1 serving of vegetables (1/2 cup): a computer mouse
- 1 serving of fresh fruit (1/2 cup): a tennis ball
- 1 serving of meat (3 ounces): a deck of cards
- 1 serving of fish (3 ounces): a checkbook
- 1 serving of cheese (1.5 ounces): a lipstick tube or the size of your thumb
- 1 serving of peanut butter (2 tablespoons): a ping-pong ball
- 1 serving of olive oil (1 teaspoon): 1 fingertip
Tips for Accurate Calorie Counting
Calorie counting isn’t an exact science, even when you weigh and measure portions. However, it’s not necessary to be entirely spot-on with your measurements. Just make sure to record your intake as accurately as you can. Try to be most careful about recording items that are high in fat or sugar, such as pizza, ice cream, and oils. Under-recording these foods can cause a big difference between your recorded and actual intake. To improve your estimations, you can try using a food scale in the beginning to give you a better idea of what a portion looks like for various foods. This can help you be more accurate, even after you stop using the scale.
Additional Tips for Effective Calorie Counting
Here are a few more tips to help with counting calories:
- Be prepared: Before you start, consider getting a calorie-counting app or online tool, decide how you will measure or estimate portions, and make a meal plan.
- Read food labels: Food labels contain lots of useful information for calorie counting. Make sure you check the portion size recommended on the package.
- Aim for slow, steady weight loss: A 2020 study found that greater weight variability at 9 and 12 weeks into a weight loss intervention predicted increased weight at 12 and 18 months from the start.
- Fuel your exercise: The most successful weight loss programs include both diet and exercise. Make sure to eat enough to still have the energy to exercise.