What Is the Minimum Calorie Intake for a 170-lb. Person to Lose Weight?

If you're 170 pounds and trying to lose weight, you can cut calories, ramp up your exercise routine or both. Your target calorie intake for weight loss will be based on your sex, activity level and height, but the minimum recommendation is 1,200 calories daily for women and 1,500 calories for men.

While fad diets and juice cleanses may promise miraculous results, the unfortunate truth is that weight loss is not effortless. In order to safely and effectively lose weight you need to achieve a calorie deficit, meaning that you burn more calories each day than you eat.

The good news is that you burn calories while at rest. The Mayo Clinic explains that your body burns calories for everything from breathing and digestion to cell growth and cell repair. The energy required for these things is known as the "basal metabolic rate," and it varies depending on your size, body composition, age and sex.

Your basal metabolic rate stays quite constant, but you do have control over how many calories you burn from exercise and how many calories you consume from food. Changing your calorie consumption and how much you burn through activity will help you lose weight.

Read more: The Best Way to Lose Weight in One Month

Harvard Health offers a math trick that can give you a sense of how many calories you need each day to maintain your current weight: Multiply your weight by 15. By that measure, a person weighing 170 pounds would need to consume roughly 2,550 calories per day to maintain their weight. Obviously, this is just a general guess, and a true weight maintenance number would depend on height and activity levels. But this calculation can give you a general idea to work from.

Once you've figured out your maintenance calorie intake, you can calculate how many calories you should consume each day to lose weight. The American Council on Exercise recommends that you set a realistic weight loss goal of 1 to 2 pounds per week. The council says that burning 3,500 calories is roughly equivalent to losing 1 pound, so an average calorie deficit of 500 calories each day can help you lose 1 pound per week.

Read more: Recommended Caloric Intake for Weight Loss

Eating fewer calories may seem easier said than done, because cutting calories can seem like a daunting task. A good first step is to keep a food diary for a few days, noting what you eat and drink and when. You can do this using a calorie counter app, the notes app on your smartphone or just pen and paper. Once you've created a food diary, you can look for patterns and identify any easy ways to cut calories from your daily diet. Some easy changes to make include:

• Decrease your portion sizes. Simply serving yourself less at meals can make a major difference to your daily calorie intake. You might find it helpful to use a food scale, so you know exactly how much you're eating. Before long, practicing portion control will seem like second nature.
  

• Focus on hydration. Make sure you're drinking plenty of water, so you don't think you're hungry when you're actually just thirsty. If you drink caloric beverages like soda or fruit juice, try swapping them out. There are tons of carbonated water options available, including calorie-free flavored options that can help satisfy your cravings for a cold, fizzy drink.
  

• Scale back your alcohol intake. Most alcoholic drinks consist of empty calories, meaning they provide calories without nutrients. The Centers for Disease Control and Prevention recommends that you consume alcohol in moderation, defined as up to one drink each day for women and two drinks per day for men. If you regularly consume alcohol, consider cutting back by a couple of drinks each week, or swapping out highly-caloric alcoholic drinks for low-calorie options.

Your daily calorie intake shouldn't fall below 1,200 calories for women and 1,500 calories for men. While it might appear logical that eating fewer calories will cause rapid weight loss, eating too few calories can actually slow your weight loss and contribute to health issues. Some potential outcomes of undereating include:

• Increased fatigue. If you're not getting adequate nutrition or are severely restricting your calorie intake, you might feel fatigued. This can affect your job performance, concentration and even your driving skills.
  

• Nutrient deficiencies. A restricted calorie intake might be short on essential nutrients, particularly vitamins and minerals. Over time, you may become deficient in B12 or iron, contributing to different types of anemia. Some deficiencies, like a lack of calcium, can contribute to long-term health issues. Low calcium levels affect your bone density and can lead to osteoporosis (brittle, fragile bones) in the future.
  

• Problems with your heart and circulation. According to the National Centre for Eating Disorders, long-term and extreme undereating can weaken your heart muscles, drop your blood pressure and slow your pulse. This can increase your risk of experiencing heart failure. Plus, slower circulation can make you feel consistently cold in your hands and feet.
  

• Slower digestion. A restricted calorie intake can affect how your stomach empties and how your digestive system absorbs nutrients, the National Eating Disorders Association says. This can lead to bloating, stomach pain, constipation, nausea, vomiting and possibly intestinal blockages.

Read more: Formula for Caloric Intake

In order to ensure you're eating sufficient calories each day while still operating under a deficit that will help you lose weight, you can speak to a doctor or dietitian about your specific needs, activity levels and weight-loss goals. Severe restriction of calories can have several adverse health outcomes, whereas following a realistic calorie deficit while eating a nutritious diet can help you safely and steadily lose weight.