The Best Way to Lose Weight in Your 30s

As you age, your metabolism gradually slows down. This means that the eating and exercise habits that helped you to maintain your weight in your twenties may not be as effective when you reach your thirties. Happily, making a few strategic changes can help you lose excess pounds in your thirties and keep them off.

Take Stock of Where You Are

• The first step toward losing weight in your thirties is acknowledging where your body is now. This means knowing how much you weigh and knowing your measurements. Muscle weighs more than fat, so while you may be laser-focused on the number on the scale, what's more important for your health and your waistline is your body fat percentage.

  Decide on a time of day that you can weigh yourself consistently; for most people, this is when they wake up. (A side benefit of weighing yourself first thing in the morning is that your weight will generally be one or two pounds lighter, since you haven't eaten anything all night and your stomach is empty.) Commit to weighing yourself daily and keeping a log of the results. It's normal to fluctuate by a few pounds due to water weight, so an increase in one or two pounds shouldn't be seen as a failure; but seeing you're three pounds heavier one week than you were the week before might be a wake-up call to hit the gym a bit harder or eat more carefully. It's much easier to stave off a problem early than after you gain 10 or more pounds.

Determine Your BMR

• Your body burns calories sleeping, sitting and breathing. The amount of calories you burn during everyday activities is known as your Basic Metabolic Rate (BMR), and this number decreases once you reach your thirties.

  Knowing your BMR can help you calculate how many calories you need to eat each day, and how many calories you need to burn through exercise, in order to lose the number of pounds needed to reach your weight loss goal.

  To calculate your BMR:

  Women: 655 + (4.35 x weight in pounds) + (4.7 x height in inches) - (4.7 x age in years)
  Men: 66 + (6.23 x weight in pounds) + (12.7 x height in inches) - (6.8 x age in years)

Understand How Weight Loss Works

• Weight loss is a rather simple calculation. If you burn more calories than you take in, you lose weight, and if you take in more calories than you burn, you gain weight.

  One pound is approximately 3,500 calories. If you burn 3,500 more calories than you take in, you'll lose one pound. Since the number of calories you burn decreases when you hit your thirties, it will take a bit longer to lose weight than it may have in the past. That means it's more important than ever to start a weight loss plan as soon as possible.

  Knowing this can help you set your weight loss goals. A safe, reasonable goal is one to two pounds per week. If your goal is one pound per week, you need to find a way--by eating less and exercising more--to burn 3,500 calories a week, or 500 calories a day.

Calculate Your Daily Food Calorie Goals

• Your BMR is a great place to start this calculation. Say your BMR is 1,500. This means that, if you do no exercise, your body burns 1,500 calories a day.

  The absolute minimum number of calories you want to eat each day is 1,200 calories. If you eat less than this, your body will think it's starving, and your BMR will drop drastically. You might lose a few pounds right away, but you'll gain it all back--and then some. Your BMR is your strongest ally in losing and maintaining your weight, and in your thirties it's more important than ever to keep it high and not to let it get any lower.

  So, if you consume 1,200 calories a day, and your BMR is 1,500, that means your body burns 300 calories a day with zero exercise. 300 calories x 7 days = 2,100 calories, or about two-thirds of one pound of weight loss each week.

Calculate Your Daily Exercise Goal

• Continuing the above example, you'll still need to burn 200 calories each day to meet a weight loss goal of 1lb. each week. This means you'll have to do 200 calories worth of exercise each day.

  Strength training is particularly important for people in their thirties. Building muscle increases your BMR, helping you burn a few extra calories each day--and over time, that adds up. Strength training can also prevent or delay the development of age-related diseases like osteoporosis. In addition, strength training exercises generally burn more calories than cardio exercises for the same amount of time.

  Determining how many calories are burned by a particular exercise depends on the intensity, length of time and your current weight. The less you weigh, the fewer calories you burn doing the same exercise. Use an online calorie calculator, such as the one found in the Reference section, to create an exercise routine that meets your calorie-burning goal.