Vitamin B12 for Weight Loss: Does It Work?


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Since the dawn of the Internet (and probably well before), there have been several solutions sold for weight management — including vitamins for weight loss. One in particular, vitamin B12 supplements, are often touted as a solution for weight management.

There are mixed claims when it comes to vitamin B12 shots or pills. Some say this supplement gives you energy and boosts your metabolism while other research has shown mixed results when it comes to weight loss.

But what’s fact and what’s fiction when it comes to this buzzy supplement? Weight loss is already a tricky subject so we’re getting to the bottom of vitamin B12 for weight loss and answering questions like:

  • What does B12 do for you?

  • Does B12 help you lose weight?

  • What is the best way to take B12?

What is Vitamin B12?

And more specifically, what does vitamin B12 do for you?

Vitamin B12, also known as cobalamin, isn’t just a popular supplement marketed to help people lose weight— it’s an essential water-soluble vitamin necessary for brain function, heart health, energy levels and more as well as forming DNA and red blood cells.

As the name implies, water-soluble vitamins dissolve in water. So while there’s no best time to take B12, you don’t need to take it with food for it to be fully absorbed.

Many foods naturally contain B12, such as:

  • Fish

  • Meat

  • Poultry

  • Eggs

  • Dairy products

Plant-based foods don’t provide B12 but fortified breakfast cereals or nutritional yeast are good sources for vegetarians and vegans.

B12 is available as either oral tablets or prescription vitamin B12 injections, sometimes referred to as B12 shots.

Benefits of B12

Is vitamin B12 good for you? Absolutely, as B12 has been shown to support brain function and additional research suggests vitamin B12 supplements (along with other B vitamins) may help improve mood disorders.

One benefit of B12 that’s been particularly noteworthy is its effects on metabolism (the chemical reactions in the body’s cells that change food into energy).

Although research is still limited, some studies suggest that vitamin B12 could affect metabolic syndrome, a health issue that includes metabolic abnormalities like insulin resistance, high blood pressure and obesity.

But does vitamin B12 give you energy? While more studies are needed to see how vitamin B12 affects metabolism in humans, there has been research on the effects of a vitamin B12 deficiency.

(RelatedHow to Reset Female Hormones For Weight Loss)

Vitamin B12 Deficiency

One example of vitamin B12 deficiencies is older adults struggling with cognitive issues and memory function.

But since you’re curious about B12 and weight loss, you probably want to know: does vitamin B12 make you gain weight?

Not quite. Rather, the question should be “Does B12 deficiency cause weight gain” as some evidence suggests low levels of B12 may be linked to weight gain and obesity.

study of 976 people found that low levels of vitamin B12 were connected to a higher risk of overweight or obesity.

Another study of over 600 young adults and children looked at the link between vitamin B12 levels and body mass index (BMI), with lower B12 levels resulting in higher body weight.

And what about metabolism, a buzzy word associated with weight loss that’s how your body gets energy from food? Does B12 increase metabolism?

Technically, B12 doesn’t increase metabolism per se. But B12 could affect your metabolism, as one study suggests that a deficiency could be linked to increased fat accumulation and obesity.

Does Vitamin B12 for Weight Loss Work?

But while these studies are promising, they’re not conclusive enough to say that vitamin B12 for weight loss works.

While lower levels of vitamin B12 are associated with higher BMI and body fat, taking vitamin B12 supplements didn’t change body composition over the long term.

More research is needed on the effects B12 has on body weight and BMI. But along with healthy lifestyle choices and weight loss medication prescribed by a doctor, B12 could play a supporting role in weight loss goals.

Vitamin B12 and Weight Loss Drugs

So does B12 help with weight loss? On it’s own, no.

Vitamin B12 for weight loss isn’t the be-all, end-all solution. The reality is that, along with other weight management tools, like medications and lifestyle changes, certain vitamins for weight loss like B12 can support a healthy weight.

Other vitamins like vitamin D and magnesium may also support weight loss, and can often be consumed via food — much like B12. Just another reason why a balanced diet is important, to ensure you’re getting all the vitamins that can help you reach your weight loss goals.

Eating more foods that contain B12 is one way to help boost a deficiency.

But if you’re vegan or vegetarian or have a medical condition like pernicious anemia (when your body doesn’t have enough B12 to produce the amount of red blood cells it needs), vitamin B12 injections may be recommended.

Vitamin B12 injections are generally safe, with few side effects and the possibility of allergic reactions.

Depending on your health and weight journey, your healthcare provider may prescribe vitamin B12 shots for weight loss alongside other medications like metformin, a diabetes medication used off-label for weight loss.

Taken as weight loss shots, there are plenty of benefits of metformin from weight management to improved cognitive function and more.

(RelatedWeight Loss Medications: Are They Effective?)

Key Takeaways of Vitamin B12 and Weight Loss

The effectiveness of taking Vitamin B12 for weight loss remains a topic of debate. There are certainly benefits of vitamin B12, whether you take it as a pill or B12 shots, along with risks.

  • B12 is a crucial vitamin necessary for wellness, supporting energy production (aka metabolism), brain function, heart health and more.

  • Does B12 help you lose weight? Research is mixed as some studies suggest deficiency leads to weight gain, while others suggest it could help weight loss efforts.

  • B12 may be combined with other medications as part of a weight loss program, such as metformin.

If you’re looking for more information on weight management or a weight loss program that’s best for you, you can seek medical advice from a healthcare provider.

This article originally appeared on and was syndicated by

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How to Reset These 10 Hormones That Affect Weight

How to Reset These 10 Hormones That Affect Weight

Hormones can be helpful heroes, supporting the immune system and a healthy sleep-wake schedule. But they can also be culprits of frustrating body issues, like excess weight that won’t come off despite your best efforts. Like many women, you might be wondering if it’s possible to reset female hormones for weight loss.

Hormones are involved in regulating body weight and the ability to achieve weight loss. Especially for women, they fluctuate throughout your menstrual cycle and during various life stages, like pregnancy, postpartum, perimenopause and menopause.

Caring for them is vital, which means living in a way that helps keep your hormones in balance.


Jump-starting your hormones to help your body shed pounds sounds appealing. And while we wish it was as simple as pressing a reset button or shocking your system with booster cables, it’s a bit more complex.

What you eat, how you move your body, whether you’re getting enough sleep and how you manage stress all play a role in hormonal balance. So by making positive lifestyle changes, you might be able to get things back on track.

If you’re wondering how to reset female hormones to lose weight and support overall wellness, this one’s for you. Let’s dig into the relationship between women’s hormones and weight loss, the main hormones involved in weight management and how to balance hormones for weight loss.


The link between hormones and weight loss is intricate and multifaceted.

Several hormones — such as insulin, leptin, ghrelin, cortisol and thyroid hormones — have significant influence over metabolism, appetite and fat storage within the body. And imbalanced hormones can mess with these mechanisms.

Understanding how they’re all interrelated can help you make changes to address a possible hormonal imbalance and work toward your weight loss goals.

Hormone Imbalance and Weight Loss

Hormone-related health conditions, like polycystic ovary syndrome (PCOS) and hypothyroidism, as well as life seasons like menopause, can lead to hormonal changes that make losing weight more challenging. 

For instance, with PCOS, high levels of insulin and testosterone can increase appetite and promote fat storage, particularly around the midsection. 

Hypothyroidism (having an underactive thyroid gland) slows metabolism, potentially resulting in weight gain despite efforts to eat fewer calories. And during menopause, fluctuations in estrogen levels can make your body hang onto more belly fat. 

If weight loss is your goal, addressing hormonal imbalances is key. This often requires a combination of lifestyle modifications, medication and possibly hormone therapy under medical supervision.

Liudmila Chernetska/istockphoto

Have you ever heard someone say, “I’m 65 today, but I don’t feel a day over 30?” Your metabolic age is sort of like that.

Whereas chronological age is simply the number of years you’ve been alive, metabolic age provides insight into how efficiently your body is burning energy relative to other people of the same chronological age.

In other words, it compares your basal metabolic rate (BMR) to the average BMR of individuals in your age group. BMR is the number of calories you’d burn each day just from being alive — or what you’d burn if you laid in bed all day without moving.

Having a metabolic age lower than your chronological age means your body is burning calories more efficiently than average — a general signal of good overall health and fitness.

On the other hand, a metabolic age higher than your chronological age could mean that your metabolism is slower than average. In that case, dietary changes or healthy lifestyle adjustments might be necessary for weight loss.

Research suggests that metabolic age can predict a person’s risk for developing metabolic syndrome, a cluster of conditions that includes abdominal obesity, high triglycerides, low “good” cholesterol, high blood pressure and high blood sugar.

Metabolic age is just one way to assess health. Still, it can be useful for understanding how your body burns calories and why it might be resisting weight loss.


We tend to focus on food intake and exercise when talking about weight — which are undoubtedly crucial — but they’re not the only factors.

Hormones have much to do with metabolism, food cravings, hunger-fullness cues and even how weight is distributed around the body. 

Several female hormone types matter for weight loss. We’ve outlined the purpose and functions of 10 hormones, along with how they’re involved in weight management for women.

(RelatedHow to Ask Your Doctor For Weight Loss Pills)


Insulin is involved in regulating blood sugar levels. It helps move glucose from blood into cells, where it can be used for energy. This hormone is also partly responsible for storing excess glucose in the liver, muscles and fat tissues. 

High insulin levels can prevent the breakdown of fat. This makes weight loss more challenging, as it tells your body to store excess calories rather than burn them for energy.

Samara Heisz/istockphoto

Leptin is produced by fat cells. It helps regulate your appetite and how much energy you burn. This hormone signals to the brain when there’s enough fat stored in the body, which tells your appetite to reign it in and your metabolism to kick it up a notch. 

Leptin resistance is associated with obesity. This is when your body may not respond properly to the hormone’s signals, leading to overeating and trouble losing weight despite having enough body fat stored.

Md Saiful Islam Khan/istockphoto

Ghrelin is a hunger hormone made by the stomach that stimulates appetite. It acts on the hypothalamus (the part of your brain that makes hormones relating to mood, hunger and body temperature) to tell you to eat.

When ghrelin levels are high — often during periods of calorie restriction or weight loss attempts — it can lead to increased hunger and potentially hinder weight loss efforts.


You’ve probably heard of glucagon-like peptide 1 (aka GLP-1), given the rising popularity of weight loss injections and obesity-management medications. This hormone is released by the intestines in response to food, especially after enjoying meals high in carbohydrates and fats.

GLP-1 is heavily involved in blood sugar management. It triggers the release of insulin from the pancreas and prevents the release of glucagon. The hormone also slows down the rate at which your stomach empties its contents, helping you feel full longer after a meal — and potentially preventing overeating.


Estrogen is best known as a primary female hormone, but it’s also involved in metabolism.

Estrogen helps regulate fat distribution and storage throughout the body, which, for women, is usually more concentrated around the thighs and hips. 

When estrogen levels are imbalanced — or when they fluctuate during life stages like menopause — it can disrupt metabolism. This could lead to unintentional weight gain.


You may know cortisol as “the stress hormone.” When your body is under stress, cortisol increases blood sugar levels to provide energy.

While this response is helpful for short-term problems, like, say, running away from a bear, chronically elevated cortisol levels can disrupt metabolism and promote excess fat storage.

Md Zakir Mahmud/istockphoto

Cholecystokinin (CCK) is released by the small intestine when fats and proteins are present in the digestive system. This slows down gastric emptying to create feelings of fullness, which may help prevent overeating.

But when your body doesn’t have enough CCK, it could increase your appetite, making it hard to create the necessary calorie deficit to lose weight.

Md Saiful Islam Khan/Istockphoto

The hormone peptide YY is released by your GI (gastrointestinal) tract when you eat protein and fat.

It acts on the appetite centers in your brain, helping your food intake stay in check by promoting fullness. Balancing this hormone may help support your weight loss goals. 

Andrii Dodonov/istockphoto

Neuropeptide Y is a neurotransmitter (brain chemical) that stimulates appetite. It aids in the storage of calories as fat and reduces the rate at which energy is burned. 

When neuropeptide Y levels are higher than normal, you may notice increased food cravings and resulting weight gain.


You might be thinking, Isn’t testosterone a male hormone? Predominantly, yes. But it’s also produced in women’s ovaries — albeit a smaller amount. 

In women, testosterone is involved in the development and maintenance of lean muscle mass. It also influences how fat is distributed in the body. Low testosterone levels may lead to more fat sitting around the abdomen.


The best ways to optimize female hormone levels for weight loss involve lifestyle changes, including eating a nutritious diet, exercising, finding ways to manage stress and getting enough sleep.

These strategies will not only support sustainable weight loss but also improve overall well-being. Here’s what you can try.

Get Active

Exercise helps support weight loss goals by burning calories, yes, but it’s also a key component of hormone management. How so? Regular physical activity triggers the release of endorphins and other hormones that reduce cortisol and overall stress.

Exercise also helps combat insulin resistance, which leads to better blood sugar regulation. What’s more, testosterone production increases when you’re active. This helps support the development and preservation of lean muscle mass while boosting fat metabolism and overall weight loss.

Your best bet for weight loss is combining a mix of cardiovascular exercises, like swimming, biking, running or group fitness classes, with resistance training and strength exercises. Resistance training has been shown to improve insulin sensitivity and blood sugar regulation.

In a study on elderly Korean women, 60 minutes of exercise multiple times a week resulted in benefits on hormonal status and physical function.

(Related: Are There Any Antidepressants That Cause Weight Loss?)

Inside Creative House/istockphoto

It’s no surprise that what you put in your body plays a significant role in your weight. Eating more nutrient-dense foods can help support normal hormone production, which could make it easier to lose weight.

Hormone-reset diets often follow a Mediterranean, vegetarian, dairy-free or otherwise plant-based diet pattern.

Choose minimally processed foods, including fruits, vegetables, whole grains, nuts, seeds, legumes and lean proteins. These foods are naturally lower in calories than ultra-processed foods (think baked goods, packaged snacks and sodas). They also provide an array of nutrients like fiber, vitamins and minerals and regulate insulin levels.


Modern living comes with an endless supply of reasons to be stressed out. This means it’s super important to figure out ways to combat stress so it doesn’t take a toll on your health — physically or mentally.

Chronic stress can contribute to hormonal imbalance and unintentional weight gain (as well as trouble losing weight).

Think about your stress triggers and what might help you overcome them. A few ideas include meditation, deep breathing, taking nature walks, listening to calming music, journaling and yoga.

Incorporating practices like these can help you avoid overeating or reaching for junk food when you’re stressed.

Daniel de la Hoz/istockphoto

Experts recommend adults get seven to nine hours of quality sleep every night. Not only does being fully rested help prevent crabbiness and trouble focusing, but it also supports hormonal balance.

Getting better sleep helps regulate the production of ghrelin and leptin, which are involved in appetite and satiety. When these hormones are out of whack, you’re more likely to overeat because your body’s hunger-fullness cues are askew. 


Weight management is a multifaceted and personal process. 

If you’re having trouble losing weight, your best bet might be talking to a healthcare provider. They can determine whether you’re experiencing hormone imbalances and, if necessary, help you figure out how to reset hormones for weight loss.

Whether it’s your primary care physician, a hormone specialist or a registered dietitian knowledgeable in female weight loss, a medical professional can tailor a plan to your specific needs.

This might involve conversations about hormone replacement therapy, intermittent fasting, supplements, weight loss medications or innovative ways to help balance hormones to lose weight.


Whether they’re being blamed for bloating and chocolate cravings during PMS or for the adult acne we thought we left behind at 17, hormones are constantly involved in many aspects of our daily lives.

Weight loss is often more than just calories in versus calories out. Balancing hormones for weight loss can be an easily overlooked factor of women’s health — but not for you!

Here’s the bottom line on female hormones and weight loss:

  • Many hormones are involved. Your hormones are always working, for better or worse, when it comes to your appetite, food cravings, metabolism and fat storage. Rather than trying to target one specific thing, a broader approach with multiple lifestyle changes might be best.

  • Strategies for hormonal balance are also strategies for weight loss. A healthy diet, better sleep, stress management and regular exercise target both weight loss and hormonal balance. This should provide some relief in the sense that you don’t have to do double the work to meet two separate goals.

  • Ask for professional help. Hormones are complex, and weight loss requires a personalized approach. A healthcare provider can help you figure out if you’re actually experiencing a hormone imbalance or if something else is going on. Additionally, a dietitian can help you create a plan forward.

This article originally appeared on and was syndicated by



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