iStock The Mediterranean diet focuses on consuming things like plant-based foods, fish, and olive oil.

The Mediterranean diet has gained popularity and it advocates eating more plant-based foods like fruits, vegetables, nuts, legumes, as well as eating fish and poultry at least twice a week.

You might not be losing weight on the diet if you’re not keeping an eye on your portions.

You could also not be losing weight if you’re not exercising or watching your red wine consumption.

The Mediterranean diet has gained popularity as a delicious way to lose weight and improve health. It advocates eating more plant-based foods like fruits, vegetables, nuts, legumes, as well as eating fish and poultry at least twice a week. The diet also involves swapping out butter for olive or canola oil, enjoying meals with others, and flavoring food with herbs and spices instead of salt.

Eating this way has been associated with a lower risk of heart disease and the lowering of “bad” LDL cholesterol, according to Mayo Clinic. The Mediterranean diet has also been linked to reduced incidence of cancer, and Parkinson’s and Alzheimer’s diseases, according to Mayo Clinic.

And even though the Mediterranean diet is known to have a host of health benefits, including weight loss, some people might find that they’re not losing much weight even while sticking to the diet.

INSIDER consulted with nutritionists, dietitians, and doctors to figure out why you might not be losing weight on the Mediterranean diet.

You’re adding too much olive oil to your meals.

iStock When used in excess, olive oil can add a lot of calories to your meal.

The Mediterranean diet encourages the use of healthy fats like extra virgin olive oil and other monounsaturated fats in place of saturated fats, such as butter and lard. However, the key to making these swaps work for weight loss is paying close attention to how much fat you’re using.

“Olive oil (and all oils) provide 120 calories and 14 grams of fat per tablespoon. Since many people use much more than that, hundreds of excess calories are consumed,” Wendy Kaplan, registered dietitian nutritionist and nutrition director at Racine Cancer Care Foundation, told INSIDER.

Even though a teaspoon or tablespoon of extra virgin olive oil will add flavour and nutrients to your dish, roasting vegetables with a quarter cup of the stuff can also add hundreds of unnecessary calories to your meal.

“When cooking your balanced meal, don’t go overboard adding extra olive oil to your food. Small amounts still provide benefits, but can keep the calories in your meal low,” Julie Stefanski, registered dietitian and spokesperson for the Academy of Nutrition and Dietetics told INSIDER.

You’re eating too many nuts without realising it.

progressman/Shutterstock Almonds are Mediterranean diet-friendly but suggested portion sizes should be considered.

Nuts are a great plant-based snack – they’re portable, tasty, and pack a hit of protein. They’re also a delicious source of the omega-3 ALA and an energy-rich component of Mediterranean diets. However, many people seriously underestimate the number of calories they’re actually consuming when they eat nuts.

“One-quarter cup of nuts typically contains 150 to 200 calories. Many people find it very easy to snack on over 1,000 calories of nuts in a sitting, so it is important to be mindful of portion sizes so that you do not sabotage yourself,” registered dietitian Summer Yule told INSIDER.

You’re drinking too much red wine or alcohol.

iStock Wine is Mediterranean-diet friendly, but that doesn’t necessarily mean you can should consume an unlimited amount of it.

For many people, one of the top selling points of the Mediterranean diet is the inclusion of red wine. It’s not necessary to drink wine to be compliant with the Mediterranean diet, but anyone who chooses to do so needs to take the calories in that wine into account.

“If you are not familiar with the nuances of this diet, it’s easy to over-consume calories from alcohol and therefore sabotaging weight loss efforts. A serving of wine is only 5 ounces and moderation means up to one glass per day for women and two glasses per day for men,” said Kaplan.

To be absolutely sure you’re not undoing your diet with a heavy pour of wine, take the time to actually measure how much wine you’re consuming and stick to the recommended daily limit for your body type.

You’re not taking other liquid calories into account.

Flickr/dancingwithwords Remember to take note of liquid calories.

Even if you’re careful about limiting the amount of red wine you drink on the Mediterranean diet, not keeping a close eye on your other liquid calories could be sabotaging your diet.

“People think of diet in terms of solid food, but 40% of our calories can come from drinks. If we have too many sweet cocktails, Frappuccinos, or supposedly healthy fruit juices, people don’t think they are breaking their diet, but they could add to calories significantly,” weight loss specialist and board-certified cardiologist Dr. Luiza Petre told INSIDER.

Just because something is marketed as being “healthy” doesn’t mean it won’t affect your waistline. Be sure to read the nutritional labels on all your pre-made drinks and opt for whole fruits and vegetables over smoothies and juices when possible.

You’re not controlling portion sizes.

Flickr/Terry Bateman Zucchini is Mediterranean-diet friendly and not overly high in calories.

The Mediterranean diet includes plenty of health-promoting foods, but it is still possible to gain weight if you’re eating more calories than you’re burning.

“The Mediterranean diet is a wonderfully healthy way to eat, but people can consume too many calories on almost any diet. Most successful weight loss diets modify both the type of food eaten as well as the amount. If you’re not doing both, you probably won’t lose weight,” clinical nutritionist Zoe Morosini told INSIDER.

Piling your plate high with diet-friendly foods can thwart your weight loss efforts if you’re not paying attention to portion size. Luckily, you don’t necessarily need a scale to figure out how much to eat on this diet.

“As you portion your Mediterranean-style plate, try to make half of it vegetables with high water content such as zucchini, eggplant, onion, and peppers. Limit the grain option to only one-fourth of your meal. Keep the protein choice to an amount the size of your palm,” said Stefanski.

You’re relying on “healthy” swaps without considering calories.

Cabeca de Marmore/Shutterstock Swapping out white rice for brown rice won’t necessarily help you cut back on calories.

There’s no way around it: when you’re trying to lose weight, calories matter. The Mediterranean diet urges adherents to swap out processed food and sugary treats for fruits, veggies, fish, and healthy fats, but it’s still important to keep track of how many calories you’re consuming.

“Calorie-loaded foods that have a healthy halo like avocado, nuts and excessive amounts of olive oil are very caloric dense and can pack fat quickly on your waistline,” said Dr. Petre.

Whole grains like whole wheat flour, brown rice, bulgur and barley are staples in the Mediterranean diet, but simply swapping out white flour and rice for brown varieties won’t necessarily save calories.

“Simply swapping whole wheat flour for white flour does not automatically denote healthy. For example, your whole grain muffin can still be oversized, providing over 600 calories and contain unhealthy ingredients,” said Kaplan.

You’re not counting calories from toppings and condiments.

lighthunteralp/Shutterstock Chances are the creamer you add to your coffee are calories you’re forgetting to take note of.

Even if you’ve memorized the number of calories in a sweet potato and have perfectly portioned your pasta, toppings and condiments can add unexpected calories to a meal.

“Your diet is not as clean and low in calories as you think. The hidden saboteurs are everywhere, from too much salad dressing to coffee creamer. There are a thousand little things that can pack on a lot of calories,” said Dr. Petre.

You’re overestimating how many calories you’re burning.

holbox/Shutterstock You might think your time on the elliptical is burning more calories than it truly is.

Unless you spend your day doing physical labour or are an active athlete, you probably won’t lose weight eating 2,000 calories per day unless you’re incorporating exercise into your routine. Similarly, simply walking up a few flights of stairs to reach your office won’t burn enough calories to qualify as a workout.

“Many people overestimate the calories they burn in a day on average by as much as 25%. Keep track and use a journal or an app,” advised Dr. Petre.

You’re focusing on diet and ignoring exercise.

Joe Raedle/GettyImages The Mediterranean diet can be more effective at weight loss if you’re also following an exercise regimen.

The Mediterranean diet is about more than just your grocery list. In order to reap the weight loss benefits of this way of eating, you can’t forget about staying active.

“Even though it is possible to lose weight by modifying diet alone, it is difficult. Adding regular exercise to any weight loss regimen increases your chances of burning more calories than you consume, making you lose weight more consistently,” said Morosini.

All weight loss plans benefits from a commitment to exercise and burning calories. In order to make the Mediterranean an effective weight loss strategy, be sure to keep your body moving.

You’re eating too quickly and not savouring your food.

iStock Salmon is a popular source of protein in this diet.

The Mediterranean diet promotes a style of eating that goes beyond what’s on your plate. Making this diet work means embracing the idea that meals are about more than just calories and nutrients. Enjoy your food by taking the time to shop for fresh ingredients, spend time cooking with friends or family, and linger at the table.

“Don’t just adopt the foods from a Mediterranean plan, take this opportunity to cultivate their attitude towards eating, too. When you focus on slowing your speed of eating down, you’re likely to feel more satisfied on less food,” said Stefanski.

To make sure you’re not overdoing it, pre-portion your nuts in plastic bags or reusable containers to make sure you can enjoy the health benefits without accidentally eating more than you meant to.

You’re stressed.

iStock Long-term stress can impact your cortisol levels.

Although diet and exercise are crucial pieces of the weight loss puzzle, scientists are starting to understand that how much we weigh can be affected by our stress levels.

“People who live with long-term stress experience high exposure to the hormone cortisol. High cortisol can increase insulin secretion and your capacity to store carbohydrates as fat,” said Morosini.

If following the Mediterranean diet isn’t helping you with your weight loss journey, it might be worth exploring stress reduction techniques like meditation or yoga. Talking to a psychologist or licensed therapist can also help resolve any emotional issues that may be stymieing your weight loss efforts.

You’re not getting enough sleep.

Africa Studio/Shutterstock Not getting enough sleep could mess with the parts of your body that regulate hunger.

So you’ve stocked your kitchen with healthy foods and are sticking to the Mediterranean diet at every meal. But if you’re not getting enough sleep at night, you could still be inadvertently thwarting your weight loss efforts.

“Often people who are stressed also experience sleep disruption too, which is also linked to an increased risk of overweight and obesity because of its ability to disrupt hormones that regulate fullness and hunger,” said Morosini.

Binging on your favourite shows late into the night might be calorie-free, but the resulting sleep deprivation could be undermining the positive changes you’ve made to your diet. Be sure to get around eight hours of quality sleep each night to help support your weight loss goals.

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