Does Biotin Cause Weight Gain?

Despite internet rumors to the contrary, biotin doesn’t cause weight gain. There's currently no evidence suggesting that taking biotin leads to weight gain (or weight loss, for that matter).

Biotin — also known as vitamin B7 or vitamin H — is a go-to for keeping hair, skin, and nails in top shape since it’s necessary to produce keratin, the protein that gives hair, skin, and nails their structure. That’s why not getting enough can cause issues like brittle nails or thinning hair.  

It’s a water-soluble nutrient, so your body excretes what it doesn’t need, meaning it’s unlikely to influence your weight in either direction.

Below, we unpack how biotin interacts with metabolism, when it might be worth taking, and what to do if you experience any side effects.

Some people hear that biotin plays a role in metabolism and think: “Great! This will help me lose weight!”

But that’s not the case. Your biotin intake shouldn’t affect weight loss or weight gain. 

There’s a link between biotin and metabolism, but it’s not what you think. Biotin helps with metabolic processes, allowing your body to effectively turn fats, carbohydrates, and protein into usable cellular energy called adenosine triphosphate (ATP).

Additionally, your body needs biotin to regulate your blood glucose levels, support your nail and skin health, and grow healthy hair. 

But there’s no research to suggest taking biotin affects your weight. Biotin is a water-soluble vitamin, so if there’s too much biotin in your body, your body will simply excrete it through your urine. 

Some people may notice weight changes while taking biotin and assume the supplement is to blame — but other lifestyle factors are usually at play.

In addition to playing a role in your metabolism, biotin helps your body produce keratin — the building blocks of healthy hair, skin, and nails. A biotin deficiency can lead to symptoms like hair loss, hair thinning, and brittle nails.  

But that doesn’t mean you need to start taking biotin supplements for hair growth (or for any other health benefits, for that matter). 

Why? Because biotin supplements only help with hair growth if you have a biotin deficiency. Biotin deficiencies are super rare — most people get enough biotin from food sources. 

If you’ve been diagnosed with a biotin deficiency, it might be helpful to take a daily biotin gummy and include more biotin-rich foods in your diet. This can support hair health. 

Biotin-rich foods include:  

• Egg yolks

• Beef liver

• Sweet potatoes

• Legumes

• Nuts and seeds

• Spinach

So unless you’re malnourished, you’re probably getting enough biotin without needing a supplement.

Although biotin is a popular ingredient in hair loss supplements, there are many types of hair loss it doesn’t help with. For example, male pattern hair loss — the most common form of hair loss in men — isn’t caused by a biotin deficiency. 

In this case, you’ll be better off trying FDA-approved hair loss treatments like minoxidil or finasteride.  

TL;DR: You likely don’t need a biotin supplement, especially if you eat a balanced diet. 

You can read more about the benefits of biotin in our guide Biotin for Hair Growth.

If you’re curious about other vitamins that might influence your weight, let’s break them down:

• Vitamin D: Whether you get in from daily sun exposure or a supplement, vitamin D is crucial for maintaining energy levels and supporting metabolic processes, specifically fat metabolism.

• Vitamin B12: Vegans and vegetarians are more likely to lack this essential nutrient that’s necessary for brain function and energy metabolism.

• Vitamin C: This one helps convert fat into energy (plus, it supports a healthy immune system).

• Vitamin E: Antioxidants like vitamin E can help combat oxidative stress, which may impact metabolism.

• Vitamin B1: You need B1 (AKA thiamine) to efficiently convert food into energy.

• Vitamin B3: B3 (AKA niacin) is another energy booster that also helps regulate cholesterol.

Keep in mind that healthy lifestyle habits might be more important for improving health and wellness than weight changes alone. They can also help support a healthy hair growth cycle.

Vitamins and dietary supplements, including vitamin B complex, can interact with medications, so it’s a good idea to speak with a healthcare professional before taking anything new.

Biotin supplements are unlikely to cause side effects. But if you’re taking supplements, you should always stick to the recommended daily dosage.

There isn’t a recommended dietary allowance (RDA) for biotin since most people get enough through diet alone. But most people can safely take up to 30 micrograms (mcg) of biotin supplements daily without experiencing side effects.

There aren’t many noted side effects of biotin. However, very high doses of biotin might impact tests that check for thyroid hormone levels, causing false positives for conditions like Graves’ disease.

The effects of biotin deficiency — that is, when you’re not getting a sufficient amount of biotin — include:

• Hair loss

• Fatigue

• Weight gain

• Digestive issues

• Mood changes

• Poor glucose (blood sugar) control

• Skin rashes

• Poor nail health

• Nervous system issues. 

If you’re experiencing these symptoms, it’s best to speak with a healthcare professional. They can order tests to check for a deficiency or underlying condition.

Noticing side effects while taking biotin supplements? Hold off on taking more and let your healthcare provider know.

Does biotin cause weight gain? No. But most people don’t actually need biotin supplements if they’re eating a healthy diet, so think twice before you buy those vitamins.

Let’s recap what we know about biotin and weight:

• Weight gain probably won’t happen if you take a biotin supplement. There’s no evidence linking biotin supplementation to weight gain (or weight loss). Your daily multivitamin isn’t a likely contributor to weight changes, either.

• A biotin deficiency can cause side effects. Fatigue, weight gain, and mood changes can happen when you don’t get enough biotin.

• But a biotin deficiency is rare. Most people get their biotin fill through diet alone and don’t need to take supplements.

If your goal is to prevent hair loss, biotin can support healthy hair growth. Biotin isn’t a proven hair loss treatment, but it won’t hurt to take it alongside FDA-approved hair loss medications like minoxidil or finasteride.

Ultimately, you don’t need to worry about your daily biotin gummy affecting your weight.

If you’re looking for additional guidance on how to stop hair loss, connect with one of our hair loss experts today for a free consultation.