There's a lot more that happens to your body besides weight loss when going on a diet.
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Following a restrictive diet plan in an effort to lose weight can be pretty enticing-as we're sure you've seen plenty of #progresspics all over social media attributed to trendy diets-but there's a lot more to consider than a diet's rules and restrictions before diving into a strict weight loss regimen.

These trendy diets, like keto and Paleo, are attractive options for weight loss, as you seemingly just have to follow a list of what (and what not) to eat to finally lose those 10, 20, even 30 pounds that you've almost given up on losing. But you might actually be losing more than just weight because of these diets, as they can lead to some major health consequences.

Below, you will find six negative side effects of some popular diets:

Digestive Issues

When it comes to following a keto or low-carb diet, slashing your carbohydrate intake also means seriously restricting the amount of fiber you're consuming each day-as fiber is only found in plant foods like fruits, whole grains, and vegetables. This alone can do some serious damage to your digestive system, causing constipation, diaherra and potentially long-term GI troubles.

On the other hand, going vegan or vegetarian-especially if you normally eat a diet heavy in processed foods and animal protein-can also cause some of the same digestive issues. Your body may not be able to handle all the fiber your body is taking in at once, so it may be a good idea to ease into increasing your fiber intake.

Constipation, gas, and stomach pains can be common side effects of trying a high-fiber diet. Luckily, this should only be a short-term issue as your body will adapt to pushing more fiber through your digestive system within weeks or days. Be sure to drink plenty of water and increase your fiber slowly.

Low Energy Levels

Even the most fit person you know spends more of their time preparing and eating food than they do in the gym, but fitness is still a big component of weight loss. Simply walking for 30 minutes a day helps torch extra calories for faster weight loss. Additionally, building muscle will also increase your daily calorie burn and improve your metabolism.

Our bodies run on carbohydrates, so you will likely experience a dip in energy if you're slashing your carb intake. While we should avoid refined flours and sugars most of the time, whole grains and fruits are extremely nourishing foods that help give our bodies energy to perform our best-whether at work or in a favorite exercise class. Restricting your carbohydrate intake can leave you feeling foggy, sleepy and even cause mood swings.

Following a calorie-restricted diet can also lead to tiredness and a lack of energy to do the things you love. If you don't feel like you ever have the energy to exercise, you might want to up your calorie intake to make sure you're taking proper care of your body. Your metabolism may even have to slow down just to keep your body functioning-and that's the last thing you want!

Developing An Unhealthy Relationship With Food

Following a very rigid diet plan-even for just 30 days-can lead to a negative relationship with food and even an eating disorder. Participating in a diet like Whole30 can skew our view of certain types of foods, seeing them as "always bad" or "always good," with no room for balance.

This can trigger orthorexia-a newly recognized eating disorder defined as an all-consuming obsession with healthy eating. Any kind of diet can trigger an obsession with food and eating (or not eating), and Whole30, keto, and vegan diets can be especially triggering with its short list of approved foods.

Additionally, counting calories can easily become an obsession, as many of us have likely experienced. It's easy for a diet to become all-consuming, especially when you're restricting your overall dietary intake. This can lead to a desire to skip meals in order to stay within your desired range, a preoccupation with food and to socially isolate yourself in order not to be tempted with higher-calorie foods and beverages. It can also skew our priorities from consuming healthy, nutrient-dense foods to foods with the lowest number of calories.

If you start to feel yourself obsessing over your food, that's a sign whatever diet you're on isn't for you and it's time to reassess and try something else.

Hormonal Problems

Since we run on carbs to function, restricting our intake can put some serious stress on our bodies-particularly on our hormones. A 2012 study out of New Balance Foundation Obesity Prevention Center found that low-carb diets can actually increase our body's supply of cortisol-that pesky stress hormone-which can negatively affect your mood, menstrual cycle and thyroid, among others.

Additionally, opting for a low-fat diet can also cause some issues with your endocrine system. Healthy fats, like omega-3's and unsaturated fats, help produce important hormones and are essential for keeping our bodies out of "crisis" mode. Severely restricting any kind of macronutrient category can lead to all kinds of health issues, particularly when it comes to your hormones.

Now when you severely restrict your caloric intake, there can be some serious long-term consequences. Consistently not eating enough can cause you to lose your menstrual cycle and can even lead to infertility. It's crucial to talk to a registered dietitian or your doctor about a healthy calorie range for your body specifically if you're trying to lose weight.

Having to Avoid Lots of Nutritious Foods

While avoiding processed foods, refined sugar and alcohol for a month could be great for your health, we aren't a big fan of the fact that you can't eat any dairy, grains, beans or soy on Whole30. Dairy and soy products are great sources of calcium and protein, while beans and whole grains are great sources of vitamins, minerals and healthy carbs for energy.

While there are people out there who don't need to consume some of these foods due to a diagnosed allergy, condition or intolerance, we believe the rest of us should feel the freedom to consume dairy, whole grains, beans and high-quality sources of soy on a regular basis. This is also true with the similar Paleo diet, which eliminates several of these nutritious food groups as well.

Going vegan or vegetarian full-time can also lead to nutritional deficiencies. While it's admirable to eliminate all animal products for the sake of your health and the environment, avoiding otherwise nutritious foods, like yogurt, chicken, and fish, means having to replace them with sources. It's important to talk to a licensed health professional before going on a diet that restricts even just one food group to ensure you're fueling your body properly.

Increase Your Risk for Chronic Diseases

The American Heart Association advises limiting one's saturated fat intake to only 10% of their daily calories-about 200 calories per day for those on a 2,000 calorie diet. This is because studies have shown saturated fat (and the foods containing it) can increase cholesterol levels and put us at greater risk for heart disease. It's pretty hard to avoid consuming high levels of saturated fat on the keto diet, and that could lead to heart health problems down the road.

On the flip side, it's easy to think you're eating healthy on a low-fat diet simply for passing on the "real" butter or cheese, but there's a lot more to it. White breads, pastas, fruit snacks and other processed but "low-fat" foods are void of the nutrition your body needs to function at its best. Eating a diet low in fat but rich in processed, sugary foods like these could lead to some serious nutrient deficiencies and increase your risk for chronic diseases, not only because your vitamin, mineral, protein and fiber intake might be lower, but also because our bodies need fat to absorb certain nutrients like Vitamins A, D, E and K.

Weight Regain

As is the case with just about anything else in life, if you severely restrict something in your diet, it's only going to make you want it more. While low-carb and low-fat diets both prove effective as a weight loss tool, we advise opting for more of a lifestyle, whether than a "quick fix" diet plan to prevent cravings, binge eating and possible weight regain.

Going keto for example is so restrictive that it can lead to cravings, and thus put one at risk for binge eating. Any diet plan that seriously restricts the consumption of an entire macronutrient group-in this case, carbohydrates-to five percent or less is highly unsustainable and will likely have you dreaming of croissants, sourdough and pasta before long (I mean, we're only human).

The Bottom Line

These diets all have shown to be effective for some people looking to achieve weight loss, but we don't advise trying them ourselves. If you like the consistency and guidance of some sort of diet plan, we are big fans of the Mediterranean Diet for both weight loss and improved overall health. The Mediterreanean Diet prioritizes whole, plant-based foods, lean proteins, whole grains and healthy fats while allowing room for celebratory foods in moderation. This is not only safer than opting for a crash diet, but the Mediterranean Diet is also more likely to help you maintain your weight instead of regaining it all (and more) a few months later!

Check out our Mediterranean Diet Center for meal plans, recipes and other resources for losing weight healthfully while reaping lots of other health benefits along the way!