Diet vs Exercise What Matters Most
Diet or Exercise? New scientific study reveals what matters when it comes to weight loss.
It’s no secret that the two most important factors in weight loss are diet and exercise. Watching what you eat is key to balancing calorie intake. Regular exercise builds muscle and boosts your metabolism. But which matters most, diet or exercise?
Studies show that what you eat has a bigger impact on weight loss than your exercise routine. If you want to lose weight, focus on eating less.
Exercise is important and will help you on your journey to lose weight. But exercise alone will not shed pounds. Weight loss comes down to calories – how many you eat and how many you burn. To take control of that, take control of your food.
To understand why your diet is so important, it is helpful to first understand how weight loss and weight gain occur.
How Does Weight Loss Happen?
Weight loss happens when you burn more calories throughout the day than you consume. The opposite is true for weight gain. When you eat more calories than you burn, you will add pounds.
Calories in food are units of energy. The calories we consume fuel our bodies so that we can think, speak, run, dance, and function. When we consume food, our bodies break down those calories into nutrients.
We also burn calories through exercise and normal everyday activity. Different activities burn different amounts of calories based on your unique body. For example, running a mile may burn around 100 calories.
Gaining, losing, and maintaining weight are all results of our daily calorie balance. There are two main ways that we can influence this balance – changing what we eat and changing our activity.
How Does Diet Affect Weight Loss?
Diet is the first and most important aspect of losing weight. By making healthy changes to your eating habits, you can stay in a calorie deficit and promote weight loss.
Many people make the mistake of drastically cutting the number of calories they consume. They think that by only eating 1000 calories per day, they can quickly shed pounds. While it’s true that you’ll need to reduce the number of calories you consume, make sure you do it in a healthy way.
Eating the correct number of calories each day will keep your metabolism at a healthy level. If you eat too little, you could actually be preventing weight loss.
Think of it this way. if you were only allowed one cup of water per day, you would probably try to save that water until you were very thirsty. Your body reacts the same way if it is only given a limited number of calories.
Your body will think you are starving and will try to preserve as much energy (in the form of calories) as possible. Your metabolism will slow down, sometimes long-term. No matter how much you exercise, it will be difficult for your body to lose weight.
Under-eating can also affect your health. Without enough calories, you will be fatigued throughout the day and may have trouble concentrating. Long-term, this wreaks havoc on your body and brain.
On the other hand, if you eat too many calories, they are stored as fat. Instead of being burned as energy, nutrients in the food store themselves around your body as fat cells. No one wants this either.
How Many Calories Should I Eat?
The number of calories you should eat daily will vary from person to person. It starts with your unique basal metabolic rate.
The basal metabolic rate (BMR) is the number of calories your body needs to accomplish basic life-sustaining functions. It takes into account your age, weight, height, and gender. This is the minimum number of calories you should be eating each day.
You can calculate your basal metabolic rate using the Harris-Benedict formula below.
- Women: BMR = 655 + (9.6 × weight in kg) + (1.8 × height in cm) – (4.7 × age in years)
- Men: BMR = 66 + (13.7 × weight in kg) + (5 × height in cm) – (6.8 × age in years)
Or use a handy online BMR calculator.
To find your ideal number of calories, you now need to factor in your activity level. Multiply your BMR by the activity factor below that best describes you.
- Sedentary: minimal or no exercise – multiply by 1.2
- Lightly Active: light exercise 1-3 days per week – multiply by 1.375
- Moderately Active: moderate exercise 3-5 days per week – multiply by 1.55
- Very Active: hard exercise 6-7 days per week – multiply by 1.725
- Extra Active: very hard exercise 6-7 days per week – multiply by 1.9
Keep in mind that if you have a physically demanding job, that counts as activity! Take that into consideration as well. An online calculator can also help with these calculations.
The final step is to adjust the number for your goals.
- If your goal is to maintain your current weight, make no adjustments.
- If your goal is to lose weight, subtract 500 calories from your daily number
- If your goal is to gain weight, add 500 calories to your daily number
500 calories each day, or 3,500 each week is a safe, healthy way to achieve your weight goals. Apps like MyFitnessPal make it very easy to calculate your daily needs and track your calorie intake.
Of course, a calorie deficit can also be caused by exercise.
How Does Exercise Affect Weight Loss?
The energy you exert while exercising burns calories. These calories contribute to your overall calorie deficit.
Each person burns calories at different rates. An athlete in peak shape will move more efficiently and burn fewer calories than someone who is just beginning to exercise. Your calorie burn also depends on age, weight, gender, and genetic factors.
Vigorous activity will burn more calories than a light activity like walking. However, both are important in your exercise routine. Experts recommend 150 minutes of moderate to vigorous physical activity each week. That’s about 30 minutes each day, five days a week.
The type of activity you do matters as well. Cardio exercises will boost your heart rate and burn a lot of calories. These are things like running or swimming. A 30-minute run can burn anywhere from 300-500 calories depending on your pace and fitness level.
Resistance training, on the other hand, may not burn as many calories in the gym, but it is still important. Lifting weights, for example, don’t get your heart rate as high. A 30-minute weight session may only burn 200 calories. But after that session, you will continue to burn calories out of the gym.
Studies have shown that resistance training boosts your metabolism and builds muscle. Both of these increase the number of calories that you naturally burn during the day.
For the best weight loss results, combine both types of exercise. Balance this with general physical activity throughout your day. Take the stairs up to your office or go for a walk after dinner. Any activity you do will contribute to a healthier you.
Balancing Diet and Exercise
Many people make the mistake of thinking they can eat whatever they want if they exercise enough. However, you cannot out-exercise a bad diet.
Regardless of the recommendations, the average American consumes more than 3,600 calories daily. If you made no changes to your eating habits, you would need to burn 4,100 calories per day to lose 1 pound a week. No matter how much you exercise, that’s pretty hard to do.
If you’re just starting a weight loss journey, the first thing you focus on should be your diet. Before you set foot in a gym, take a look at what you eat.
Are you eating too many processed foods or sugary drinks? Are you eating enough fresh fruits and vegetables? Are your portion sizes too big? Altering these important dietary factors will produce big results on their own.
Once you are regularly eating a healthy diet, then you can begin adding in exercise. If you’re new to working out, start small. Begin by walking every day or doing yoga. As you feel comfortable, you can do more intense activities.
The 80/20 Rule
A good rule of thumb to follow is the popular 80/20 ratio. Aim for weight loss that comes 80% from your diet and 20% from exercise.
If your goal is to lose 1 pound per week, that’s roughly 3,500 calories that you’ll need to cut. 80% or 2,800 should be cut in your diet. The other 20%, or 700 calories, can be burned through exercise.
If you exercise four times a week, try to burn 150-200 calories at each workout. Then, cut 400 calories from your diet each day by making healthy swaps.
Many people find that this is a much easier strategy to follow than trying to burn 500 calories a day through exercise or diet alone. It’s a sustainable, healthy weight loss method with lasting results.
There is so much advice on the internet about losing weight and living healthy. It can be hard to know where to focus your energy. As you embark on your weight loss journey, focus on your diet first. Then add in exercise to take it to the next level. This balance will keep you looking and feeling great.