Have you ever been on an extreme diet where you lose weight rather quickly at first, but over time it becomes harder to lose weight and it becomes very difficult to stick with your diet because the hunger pangs intensify?
Many popular diets suggest very low calorie consumption. They recommend women to eat 800-1,200 calories per day, and men to eat 1,500-1,800 calories per day. These diets are appealing because they can make you lose weight quickly at first, even though they lead to failure in the long run.
Many experts don’t recommend extreme diets as a way to lose fat and neither do we. There are at least 9 reasons why you should avoid extreme diets if you want to lose fat permanently.
1. Extreme Diets Slow Your Metabolism
When you drastically reduce your food intake, your body will sense starvation. It will then activate the starvation response in your body. The starvation response is a set of adaptive mechanisms to protect your body from starvation by slowing down your metabolism and burning less fat.
This is the reason why people who are dieting experience rapid weight loss at first, but then they find it harder to lose weight. It’s because their metabolism slows down. The technical term for this is ‘Adaptive Thermogenesis.’ If their activity level stays the same, they’ll burn less fat than before.
2. Extreme Diets Lower Your NEAT
Non-Exercise Activity Thermogenesis (NEAT) refers to the calories you burn while doing regular physical activities (excluding sports like exercises). This involves normal living activities such as walking, typing, working, shopping, driving, and so on.
Extreme diets will make you lethargic. Then your activities will decrease due to easy fatigue. When your activities decrease, your NEAT will decrease. When your NEAT decreases, you will burn less fat than before. In simpler terms, a hungry person is less active, which makes her/him burn less fat.
3. Extreme Diets Reduce Your Exercise Capacity
Extreme diets do not go hand in hand with good workouts. If you want to perform exercises that will burn your fat and sculpt your body, then you need enough energy. Extreme diets, as we have mentioned above, cause lethargy. This will certainly affect your strength, concentration, and thus your workout performance.
4. Extreme Diets May Lead to Muscle Loss
If you starve your body, it will try to find ways to preserve energy. One way is by disposing of muscle because muscle burns energy and it’s an extra weight that your body must carry around. Lean individuals whose body fat is already low have a higher risk of losing muscle, but anyone can run into it.
When you diet without doing resistance training, 30-50 percent of the weight you lose could come from the loss of lean body mass. The risk of losing muscle can be greater if you eat too little protein. Even if you eat enough protein and lift weights, but you also go on an extreme diet, some of your lost weight may still be muscle.
5. Extreme Diets Lead to Excess Hunger and Cravings
When you’re on a diet, one of the first things you’ll notice is hunger. It’s normal to feel a little hungry when you’re running a calorie deficit, but extreme diets lead to ravenous cravings. It’s nearly impossible to stick to a diet that keeps you struggling with ravenous hunger pangs and thinking about food nonstop.
There are quite a lot of hormones that influence your feelings of hunger or fullness. Also, your eating desire can be either environmental or psychological. People tend to want what they can’t have, so with an extreme diet that severely limits your calories, you’ll tend to feel the need to binge and crave foods you can’t have. It will be even worse if you’re constantly surrounded by foods that tempt you.
6. Extreme Diets Reduce Thyroid Hormones
The thyroid is a small gland in your neck. It produces at least two hormones that regulate your metabolism, i.e. triiodothyronine (T3) and thyroxine (T4). Hence, thyroid hormones affect your capacity to burn fat.
Doing an extreme diet could reduce your T3 and T4 hormones. Since both hormones serve to keep or speed up your metabolism, reduction in both means reduction in your capacity to burn fat.
7. Extreme Diets Increase Cortisol
Extreme diets could cause or increase stress. When you’re on an extreme diet, you’re constantly trying to resist temptation and the feeling of being hungry. You also need to monitor your calorie intake every day. These activities create negative emotions or stress.
When you’re stressed, your cortisol level will increase. Cortisol is a hormone secreted by your adrenal glands when you’re experiencing mental and physical stress. It reduces your body’s ability to build muscle. Hence, extreme dieting could make it difficult for you to build muscle and burn fat.
8. Extreme Diets Decrease Testosterone
When you reduce too many calories from your diet, your testosterone is also going to dip. From the “survival of the fittest” perspective, this makes sense given that testosterone is the primary male sex hormone. If you’re unable to feed yourself, you wouldn’t have the ability to feed any offspring, would you?
Research published in the Journal of Applied Physiology found that US Army Rangers who were in a calorie deficit of about 1,200 calories per day with sustained workload, inadequate sleep, and thermal strain, had their testosterone fell near the castration level.
The vast majority of studies have suggested that cutting calories by 20% below your maintenance level will not affect your testosterone. But, if you cut calories more aggressively and you keep getting leaner, your testosterone levels can drop.
9. Weight Regain Through Extreme Dieting
When you begin an extreme diet, you’ll tend to lose weight rather quickly. But the weight loss will eventually slow down or stall, and the hunger will intensify. At this point, most people will give up. Many will end up binge eating because their hunger is so severe.
That’s awful because the diet makes your body easier to gain weight. So, you can end up fatter than before you began the diet. You’ll then be tempted to follow a new extreme diet, and start the journey to the yo-yo cycle again.
This cycle of weight loss and regain is called weight cycling. A lot of people suffer from this for many years, sometimes even for their whole lives. This is a very unhealthy practice that can wreck your metabolism. Each cycle will make your metabolism less effective, so you can gain weight more easily even though you eat less than before.
The Solution: Moderate Diet
As you can see, it is very hard or nearly impossible to lose fat with extreme diets. Biologically, extreme diets will make your body more difficult to burn fat and build muscle. Psychologically, it’s almost impossible to stay long on extreme diets. You’ll most likely give up on your diet when you hit a plateau and your hunger gets worse.
This doesn’t mean you shouldn’t go on a diet at all. If you want to lose fat, you must create a calorie deficit. A calorie deficit means that the number of calories you consume is less than the number of calories you burn. This means you have to go on a diet, but your diet should be moderate, not extreme.
We recommend a calorie deficit of 15 to 30 percent below the maintenance level. For example, if you choose a calorie deficit of 20 percent, and you’re an average female with a maintenance level of 2,100 calories per day, a 20 percent deficit is a 420-calorie reduction. This gives you a goal of 1,680 calories per day. If you’re an average male with a maintenance level of 2,800 calories per day, a 20 percent deficit is 2,240 calories per day.
However, this is not a rigid prescription. There are conditions where one must make a larger deficit. For example, a severely obese person with a life-threatening situation may need a larger deficit to lose fat quickly. But for most people, moderate dieting is the safest and healthiest way to lose fat.
To become successful in your fat loss efforts, you should choose a plan that you can commit to for the long-term. A moderate diet is easier to follow and stick with for the long haul. In the process, you’ll also develop new healthy eating habits. Once you’ve lost the fat, you can increase your calories gradually to the maintenance level and keep the healthy eating habits you’ve learned. If you want to lose fat and get lean permanently, this is the way to go.