Whether you are trying to lose weight, gain weight or just manage your weight, the amount of food you eat is the most important thing to consider. It may seem like a no brainer, but many of us get this part wrong. It’s easy to get caught up in the overwhelming amount of diet advice and quick-fix solutions on the internet, but dieting doesn’t have to be complicated.
At the most simplest level, your body runs off energy in the form of calories from foods and beverages. You need this energy to fuel your daily needs and to survive. If you get the exact number of calories you need each day, you will maintain your current weight. If you eat less than what you need, you will lose weight. And if you eat more calories than you need, you will gain weight. Weight management is a basic formula diet plan of calories in versus calories out.
The calories you get from foods and beverages mainly come from macronutrients or “macros”. These macros include carbohydrates, protein, and fat. Carbohydrates and protein provide roughly four calories per gram - meaning a food or beverage item with 10g of protein will provide 40 calories from protein. Fat is the most calorically dense macro and provides nine calories per gram, so a food or beverage containing 10g of fat will provide 90 calories from fat - more than twice the amount of energy as protein and carbohydrates. Alcohol also provides a significant amount calories - in fact, each gram of alcohol provides seven calories per gram. Learning to track your macros can help you manage your calorie intake.
Because you aren’t constantly eating and you don’t immediately use all of the calories you eat for energy, your body has an efficient way of storing carbohydrates in your muscles and liver, and fat throughout your body as reserve fuel. Kind of like putting gas in your tank. Your body does not have an efficient way to store protein, instead it gets used for energy or broken down for other really important bodily functions.
Whenever your body needs energy on demand, it can use your reserve fuels, getting roughly the same amount of energy you would if you consumed macros. In other words, burning one gram of stored carbohydrates provides four calories of energy, and one gram of bodily fat provides nine calories of energy. Because breaking down fat for energy provides the most calories for the least amount of work, your body naturally prefers to burn fat for energy when you are in a calorie deficit. In other words, cutting the right calories may help you lose fat.
Micronutrients, such as vitamins and minerals, may also play a role in weight management but do not directly contribute to calorie intake.
How Many Calories Do You Need Per Day?
Calorie needs can differ drastically from one person to the next. The exact amount of calories you need can vary depending on age, height, gender, weight, percent lean muscle mass and level of activity.
The best place to start when calculating your individual needs to promote fat loss, is to determine the following:
- How much do you weigh now?
- How much weight do you want to lose?
- How much are your planning to exercise?
With this information you can figure out how many calories you will need to eat to using an online calculator or these four steps:
Step #1 - Estimate your minimum energy needs based off your current weight.
This is the least amount you would need to eat to maintain your current weight and keep on surviving, if you did not move around during the day or exercise at all. This is called your Basal Metabolic Rate or BMR, and can be quickly estimated using one of the following:
Meet Joe and Jenny. Joe is a 35 year old male who works a desk job and is looking to lose about 25 pounds this year so he can get back to his college weight. Jenny is a 26 year old female student, who works out occasionally and wants to lose about 20 pounds for her upcoming wedding in 3 months.
Joe weighs 225 pounds will need a minimum of 2,475 calories per day (225 lbs. x 11 = 2,475)
Jenny weighs 160 pounds will need a minimum of 1,600 calories per day (160 lbs. X 10 = 1,600)
Step #2 - Assess how much physical activity you are getting each day.
Moving around throughout the day and working out will increase the amount you are burning and, thus, increase the amount of calories you need to eat to maintain your weight. To calculate your Total Daily Energy Expenditure or TDEE, you will need to estimate how much physical activity you currently get each week. Even if you are planning on increasing your physical activity to help cut calories in the future, it is important to calculate your activity level based on your current workout schedule. Use the chart below to find the right activity factor for you:
Step #3 - Calculate the total amount of calories you need each day to stay at your current weight.
Simply multiply your minimum calorie needs from step one by your activity factor to get your estimated total daily energy expenditure (TDEE).
Joe gets very little exercise and sits at a desk all day, giving him an activity factor of 1.2 and a TDEE of 2,970 calories per day (2,475 calories x 1.2 activity factor = 2,970)
Jenny is moderately active with an activity factor of 1.375 and has a TDEE of 2,200 calories per day (1,600 calories X 1.375 = 2,200)
Step #4 - Determine how many calories you should eat to reduce your weight, based on your TDEE.
For most individuals eating 15-20% less than your recommended daily calorie intake, or TDEE, will promote healthy decrease in weight that is sustainable. Cutting too many calories can end up doing more harm than good. Use one of the following options or somewhere in between the two that works best for:
Sustainable weight loss = TDEE x 0.85
Fast Weight Loss = TDEE x0.8
Joe is looking to finally shed some pounds and keep it off for good, so he is taking a sustainable approach that he knows he can stick to. Joe has a TDEE of 2,970 and when counting calories should aim to eat 2,525 calories per day to lose weight. (2,970 x 0.85 = 2,525) * 15% calorie decrease
Jenny is looking for a more aggressive approach to weight reduction to get in shape for her upcoming nuptials. With a TDEE of 2,200, she should aim to eat 1,760 calories per day. (2,200 x 0.80 = 1,760) * 20% calorie decrease
How Many Pounds Can You Lose per Week?
Now that you have an idea of how many calories you need to eat to lose weight, you can figure out how much weight you should be losing each week. In order to lose one pound, you need to cut about 3,500 calories from your diet. This also means eating 3,500 calories extra can cause you to gain a pound.
Since cutting 3,500 calories in a day or two is not realistic or even possible for most people, it is best to spread out your calorie deficit throughout the week. You can cut 3,500 calories by decreasing your calorie intake each day, or increasing the amount of calories you burn through physical activity. In other words, in order to lose one pound per week you will need to cut 500 calories per day from either food, exercise or both combined. And for two pounds lost per week, you would need to cut 1,000 calories a day.
Depending on your current weight and calorie needs, a loss of 0.5 to 2 pounds per week represents a healthy rate of reduction in weight.
Joe is cutting 445 calories per day and will lose a little less than one pound per week from diet alone. (2,970 TDEE - 2,525 calories for sustainable weight loss = 445 calories cut per day). Joe is doing well on his diet and decides to add 30 minutes of moderate exercise daily, with a calorie burn of 300 calories. His new workout routine would increase his calorie deficit to 745 calories per day, which would equal about one and a half pounds of lost per week. At this rate, Joe can expect to reach his goal weight in a little over 4 months.
Jenny is cutting 440 calories per day and will lose a little less than one pound per week from diet alone. ( 2,200 TDEE - 1,760 calories for weight loss = 440 calories cut per day). Although she is taking a more aggressive approach to calorie cutting than Joe, she is starting at a lower weight and TDEE which can slow down her rate of weight lost in comparison. She decides to add 45 minutes of hard exercise daily, with a calorie burn of 550 calories each time. Her added workout routine would increase her overall calorie burn to 1,000 calories per day, which would equal two pounds of weight lost per week. At this rate, Jenny can expect to reach her goal weight in about 3 months - just in time for the wedding!
There are many different ways to measure the success of your diet, the scale is just one of them.
How Low Can You Cut Your Calories?
Cutting the most amount of calories possible from your diet may seem like the fastest and most effective way to lose weight, but cutting too many calories can often do more harm than good. Because your body requires calories for survival, very low calorie diets can put your body into a state of starvation. When your body goes into starvation mode, it starts preserving fat stores for future energy and breaks down lean muscle instead. This effect will not only affect your lean muscle mass, which is important for maintaining a healthy fat burning metabolism, but also slows down the rate of calories that your burning. Meaning you will be burning less fat and less calories total.
Most dieters should strive to keep their intake above 1200 calories per day for women and 1800 calories per day for men. Eating less than these amounts or cutting more than 25% of your current calorie intake may cause your body to go into a state of starvation.
Stick to your 15-20% decrease from your estimated TDEE. You will be much happier and more successful with a more measured and sustainable diet plan approach.
Your body needs energy to survive, but you also need good nutrition to live well, and longer. While the quantity of what you eat will determine overall weight loss, gain or maintenance, the quality of what you eat also plays a important role. The overall balance and nutrition of your diet, can affect the type of weight you lose, gain or maintain. If your macro balance is out of whack you could be storing more fat or losing muscle mass, which can hinder your overall efforts.
In addition eating more nutrient dense foods may promote losing more weight and control hunger (1). When your body is not getting the nutrition you need or is deficient in key nutrients, it signals to your brain that you need to keep eating, regardless of how many calories you’ve consumed. Make your calories count and choose the most nutrient dense foods for optimal and healthy weight reduction.
To easily track your daily calorie intake and overall nutrition, check out the Trifecta App!
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