Metformin For Weight Loss: Does It Really Work?


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When it comes to weight loss, there are a number of tried and true lifestyle changes you can make to help you along the way. But sometimes, those extra pounds are as stubborn as a toddler who doesn’t want to go to bed.

We all know the dangers associated with carrying excess weight, and given that the obesity prevalence among adults was nearly 42 percent from 2017 to 2020, it’s no surprise that weight loss drugs like Wegovy and Ozempic have become increasingly popular.

You may have also heard that metformin, a diabetes drug for managing blood sugar levels, can help you lose weight. But is it true?

What Is Metformin and How Does It Work?

Metformin is an FDA-approved medication for people with type 2 diabetes mellitus, a common condition in which the body doesn’t produce enough insulin.

Off-label, metformin is also used to manage gestational diabetes (a type of diabetes that develops during pregnancy) and treat polycystic ovary syndrome (PCOS). It’s also the only diabetes medication recommended for prediabetes by the American Diabetes Association (ADA).

Exactly how it works isn’t quite clear but researchers believe the medication causes your liver to lower the amount of glucose it makes and releases into your bloodstream.

In other words, metformin helps your body respond better to the insulin it makes and decreases the amount of glucose that your intestines absorb. This helps keep your blood glucose levels (or blood sugar levels) in a healthy range, which can help prevent serious health issues like heart disease and loss of vision.

Metformin can cause side effects, like any medication. Common side effects of metformin include diarrhea, nausea and vomiting.

Although less common, some people may have chest discomfort, headaches, sweating, hypoglycemia (low blood sugar) and weakness. 

An even less frequent, yet severe, side effect of metformin is lactic acidosis, or a buildup of lactic acid in the blood. This happens when there’s not enough oxygen in the muscles to break down glucose.

But back to the question that’s probably on your mind right now: can metformin cause weight loss? The short answer seems to be yes: people using this medication may experience a reduction in body fat.

(Related: Weight Loss Medications: Are They Effective?)

How Does Metformin Cause Weight Loss?

When metformin was tested in a large study on patients with diabetes, the researchers also noticed a significant decrease in weight and waist measurements.

In this study — the Diabetes Prevention Program Outcomes Study from 1996 to 1999, to be specific — patients took either metformin or a placebo.

Not only did metformin reduce diabetes by 31 percent over three years, but follow-up studies found that those taking the drug also lost 3.8 kg (or 8.4 pounds) after 29 weeks of treatment and had reductions in waist circumference.

A more recent 2020 meta-analysis of 21 trials testing metformin found the drug had a modest effect on lowering body mass index (BMI) — a measure of body fat based on height and weight, with a BMI of 30 kg/m or more defined as obese. This effect was biggest for those who were considered to have obesity.

Furthermore, a smaller study on metformin for weight loss found that the average amount of weight lost in 154 patients was between 5.6 and 7 kg (that’s roughly between 13 and 15 pounds).

So, although its FDA-approved purpose is to help blood sugar control, there’s definitely promising evidence that metformin treatment could work to help reduce excess body weight. And experts have some ideas as to how metformin for weight loss works.

One theory is that metformin works as an appetite suppressant, both directly and indirectly. Metformin, like Wegovy and Ozempic, increases secretion of the hormone GLP-1, which sends a signal to your brain that you’re full and helps reduce calorie intake.

Metformin may also make you more sensitive to leptin, a hormone that helps control appetite.

Another idea behind metformin-related weight reduction is that the medication promotes insulin sensitivity.

The food we eat is converted into glucose or sugar, and when glucose enters the bloodstream, your pancreas releases the hormone insulin to provide you with energy.

Some people’s bodies may fail to efficiently use or store glucose. This is called insulin resistance, and your body creates more of the hormone to try and compensate for higher glucose levels.

These higher blood sugar levels can eventually lead to prediabetes and type 2 diabetes.

Metformin has been shown to increase insulin sensitivity — AKA reduces insulin resistance — and make sure your body is getting energy from your food intake.

Another way metformin may prevent weight gain? By producing short-chain fatty acids that alter your gut microbiome, which can improve metabolism and suppress appetite. These changes to your gut microbiome can also lead to gastrointestinal issues like stomach pain, but the bright side is that this can further reduce your appetite.

What is the Dosage of Metformin for Weight Loss?

Being overweight or having obesity can raise your risk for type 2 diabetes, and losing weight may help prevent developing diabetes, according to the American Diabetes Association (ADA).

Although it’s not an FDA-approved weight loss drug, you can see why some healthcare providers prescribe metformin off-label for weight management. But what’s the right dosage of metformin for weight loss?

For diabetes treatment, the ADA recommends 850 mg once a day for one month, with the possibility of increasing the dosage to twice daily, to be taken at the same time. But for weight loss, the dosage may be different.

Whatever the reason you’re taking metformin, it’s important to start low and go slow, and work with a professional. Your dosage will depend on your medical conditions, how much you weigh, your kidney function and more. Your provider is likely to start you on a smaller dose to help your body acclimate to the medication, and reduce the severity of side effects.

Seeking medical advice from a healthcare provider is the best way to find which dosage of metformin for weight loss and/or diabetes prevention is best for you.

(Related: Can Sleep Affect Weight Loss?)

The Verdict on Metformin for Weight Loss

With the use of weight loss drugs on the rise, it’s no surprise that metformin has entered the discussion. But can metformin lead to weight loss?

  • Metformin, which is approved by the FDA for type 2 diabetes, works to decrease high blood sugar levels. While not designed to be a weight loss drug, research has found a connection between metformin and weight loss.

  • Being overweight or having obesity can lead to diabetes, which may explain why healthcare providers prescribe metformin for weight loss to prevent prediabetes or type 2 diabetes.

  • Researchers believe that metformin weight loss occurs because the drug promotes insulin sensitivity, which allows glucose from the food you eat to be properly converted to energy or stored. There’s also a theory that metformin works as an appetite suppressant by increasing your levels of the hormone GLP-1.

While more research may be needed for full FDA approval as a weight loss medication, there’s a lot of evidence that metformin can lead to weight loss, and it’s often prescribed off-label for this reason. Hers offers access to metformin for weight loss as part of a holistic weight loss treatment program, after a consultation with a healthcare provider.

But whether or not you go the metformin route, healthcare providers recommend plenty of other tried and true habits to shed extra pounds, such as eating a healthy diet, getting regular exercise like walking, aiming for seven to nine hours of sleep and more.

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25 Weight-Loss “Tricks” You Should Stop Immediately

25 Weight-Loss “Tricks” You Should Stop Immediately

When it comes to diet and nutrition, we all want to find “the answer” that will fix our alleged problems. As a result, we often latch onto crazy diet ideas that, in the moment, sound like the perfect solution. But these too-good-to-be-true “solutions” can hurt more than help us in our attempts to achieve weight loss and gain healthy habits.

Here are some of the most common diet myths exposed.


The protein-pushing keto craze sure makes it seem like carbs should be avoided at all costs. But do grains deserve their bad reputation?

“People often say that carbs are fattening,” says Kristin Kirkpatrick, MS, RD, LD. “But complex carbohydrates, like whole grains, are not ‘fattening’ foods.’”

In other words, avoid refined carbohydrates like white bread, rice and processed snacks, but keep those whole grains for a healthy balance.

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While diet sodas may be a better alternative than their full-sugar counterparts, medical studies are starting to show that the artificial sweeteners may actually cause us to eat more calories later in the day. If you want to keep the fizz and ditch the artificial sweetener, try flavored carbonated water instead.

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Like carbs, the type of fats we eat makes a difference. That, in combination with how many calories we eat each day, determines our body weight. Trans fats, typically found in many fried foods, can cause cardiovascular disease. However, saturated fats do not have the same effect and can, in fact, help keep us satisfied longer, leading to fewer calories consumed.

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Maybe you’ve only been eating the egg whites to avoid raising your cholesterol. Well, maybe you don’t have to anymore.

“Unless you are genetically predisposed to high cholesterol or cardiovascular disease, eating the eggs AND yolks can actually help you,” says Darin Hulslander, CEO and owner of DNS Performance and Nutrition. “For one, yolks are high in antioxidants, vitamins, and minerals. Egg yolks also elevate high-density lipoproteins, which are the ‘good’ proteins that can help remove plaque from the arteries.”

If you count calories, you might think losing weight is as simple as staying under a certain number every day. Unfortunately, this is not necessarily true. You can eat 200 calories of lean protein or 200 calories of chocolate, but the body processes each differently. Depending on what you eat, your body can store or burn more calories. So, use those calories wisely!

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Reading headlines such as “red meat could lead to cancer” is frightening. And while some studies indicate there is an association with red meat consumption and cancer, it’s important to note that this doesn’t mean it causes cancer. Eating red meat in moderation is not dangerous.

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The American Heart Association recommends that people consume less than 1,500 milligrams of sodium (salt) each day. Excessive sodium can lead to high blood pressure. However, this doesn’t mean we have to eat bland food. Use salt in moderation and, if you have high blood pressure, talk with your doctor on the best guidelines for your individual needs.

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Sure, peanut butter is a good source of protein and fat. However, you need to be careful about what kind you put in your pantry. Many national brands of peanut butter are filled with extra sugar, fats and preservatives that counteract any health benefits. Check the label and pick up a jar with as few ingredients as possible to get the healthiest version of this favorite snack.

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Calories can’t tell time. The time of day of when you eat only matters if you tend to overindulge at the end of the day and eat too many calories. If you happen to eat a late dinner or snack but stay within your normal calorie range for the day, it should all even out in the long run. However, many people mindlessly eat at night because they are bored or tired, and this is what leads to weight gain.

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This is the one case where all calories are pretty much alike. Multiple studies show that eating the same amount of calories in either a few larger meals or more frequent smaller ones have the same outcome on the body. In other words, this is a case where 1,000 calories in a day are the same, no matter how often you eat during the day.

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With labels like “Lean Cuisine” and “Healthy Choice,” it’s easy to think that pre-packaged frozen meals are not only convenient but also a better choice to help us in our diet goals. This isn’t always the case. Many of these pre-packaged meals contain too much sodium, which can lead to water retention and bloat. Also, many offer too few calories, which can lead to hunger later on in the day. Check the labels carefully and make sure you’re making the best choice.


When looking to avoid processed carbohydrates, many people reach for wheat or multigrain bread over white. But be careful! Make sure you’re picking up 100% wheat or whole grain bread. Otherwise, you could be just be getting mostly white bread with a little wheat flour mixed in — or even just food coloring to make it look brown!

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This nutrition myth has been around forever, but it’s just not true for most people. Medical studies show that among extremely active people such as marathon runners and skiers, taking at least 200 milligrams of vitamin C every day can possibly cut the risk of getting a cold in half. But for most people, taking daily vitamin C did not seem to actually reduce the risk of getting a cold.

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Wouldn’t it be great if there were such a thing as a negative-calorie food? You know, the kind that burns more calories when we eat it than it has? Sadly, there is no such thing, even when it comes to something as healthy as a piece of celery.

“Regardless of the [calories] in the food, you’re always going to be able to get something out of it,” says Stephen Secor, a professor of biological sciences at the University of Alabama.

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Organic is simply how ingredients are grown, usually pesticide-, herbicide- and insecticide-free. An organic label does not mean it’s healthier than non-organic foods. Even things like sugar, granola bars and boxed mashed potatoes can be organic. So, don’t rely on an organic label to tell you if something is automatically better for your diet.

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While cutting out gluten from your diet can help if you have celiac disease, it isn’t really a factor in weight loss.

“Unless you suffer from celiac disease, there’s not much scientific support to back the claim that eating gluten-free is healthier or a smart strategy for weight loss,” says Ashvini Mashru MA, RD, LDN. “Cutting gluten out of your diet most often leads to a reduction in overall calories, simply due to the sheer amount of grain-based foods that we eat on a regular basis.”

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Fewer calories consumed means weight loss, right? Not so fast!

“In fact, studies have proven it to be the opposite: skipping meals promotes weight gain,” says Cheryl Forberg, RD, nutritionist for “The Biggest Loser.” “When we skip a meal, by the time we eat, we’re so hungry we consume too much, too fast and choose the wrong foods.”


Foods like asparagus and lemons are known as natural diuretics. And while these kinds of foods may not hurt when it comes to holding onto excess water, eating large amounts of them will not help get rid of belly bloat or weight.

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Your daily cup of coffee may give you a good dose of caffeine, which is a stimulant to your body. However, that caffeine jolt does not boost your metabolism enough to be a weight loss cure-all. Also, depending on what you add to your coffee (cream, flavorings, sugar), you could be adding extra calories to your day. So if you love a cup of joe, keep it basic and black, if possible.

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This is a short-term fix with many long-term problems. By severely cutting daily calories for extended periods of time, your entire metabolism can change to actually hold onto weight! Also, your body needs adequate nutrition to stay healthy. If you want to lose weight and keep it off forever, you need a modest calorie restriction plan that you simply continue and never stop.


You cannot outrun a bad diet. It’s as simple as that. Exercise is great for our cardiovascular health and for building good muscle tone. And yes, it does help regulate our weight. But the amount of exercise you have to do to counteract a few extra slices of pizza isn’t sustainable or reasonable. So work in a healthy diet plan along with your regular workouts for optimal results.

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In a pinch, these convenience items are helpful in maintaining a healthy diet. But things like shakes and nutrition bars are not meant to be long-term replacements for healthy meals. Check the ingredients for artificial sweeteners if you buy these items. Your best bet: Make these at home and use them occasionally.

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Yes, some people should probably cut back on sugar in order to make their diet healthier. But naturally sweet foods such as fruits are sources of important vitamins and minerals. The sweets to avoid are those with added sugars and syrups.

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Good news! While fresh vegetables are always a healthy option, so are most frozen varieties. Over time, fresh vegetables can lose nutrients, while frozen ones can retain them longer. Make sure you pick up frozen vegetables without added sauces, cheese or sodium to keep them as close to fresh as possible.

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Can you imagine life without ice cream, cookies or cake? You don’t have to in order to follow a healthy eating plan. In fact, planning to have some of your favorite treats occasionally can ensure you don’t feel deprived and end up splurging later on.

This article originally appeared on TheDelite and was syndicated by MediaFeed.

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Featured Image Credit: shurkin_son/istockphoto.