What happens if you take metformin when you don't necessarily "need" it?

Doctors prescribe metformin for the treatment of type 2 diabetes and gestational diabetes. Metformin has been shown to reduce death and complications from diabetes by 30%. Aside from its use in treating diabetes, metformin may also be beneficial for people with obesity, cardiovascular disease, and cancer.

A man taking a pill

Key takeaways

  • Metformin is a medication primarily prescribed by doctors for managing type 2 diabetes and gestational diabetes (diabetes that develops during pregnancy).
  • However, it can be used as an “off-label” to treat other conditions such as prediabetes, obesity, cardiovascular disease, and even cancer.
  • Metformin is generally well-tolerated, but it can cause side effects such as nausea, diarrhea, and abdominal discomfort. Taking it for a longer time may pose serious side effects, such as vitamin B12 deficiency.
  • Self-medication with metformin or any medication is strongly discouraged. The best approach is to consult a healthcare professional who will assess you, run appropriate tests, and consider your medical history before prescribing metformin.

Metformin (Glucophage) is a medication commonly prescribed for the treatment of type 2 diabetes and gestational diabetes (diabetes that develops during pregnancy). It is sometimes used in the prevention of type 2 diabetes in people who are at high risk.

Doctors often prescribe this medication when lifestyle modifications alone have not been able to control blood sugar levels.

Metformin works by lowering blood sugar levels. It improves the way your body responds to insulin, a hormone that helps the body metabolize sugar (glucose). Metformin also reduces the ability of the liver to produce glucose, improves insulin sensitivity, and slows down glucose absorption.

Metformin is usually taken orally, typically with meals or as directed by a healthcare professional. It is safe and affordable and is available in tablet, liquid, and powder sachets. 

This article will answer the question, “What happens if you take metformin when you don't necessarily need it?” It will also discuss other benefits of metformin besides treating type 2 diabetes.

What happens if you take metformin when you don’t have diabetes?

Metformin is primarily used as a drug for treating diabetes. However, it may still benefit people without diabetes who don't necessarily need to stabilize their blood sugar levels.

Here are other potential benefits of metformin, even for people without diabetes:

1. It helps reduce the spread of tumor cells

Metformin has shown potential benefits for people with cancer. Research has shown that it inhibits the growth, survival, and spread of tumor cells in various cancers. This includes breast, liver, bone, pancreas, endometrial, colorectal, kidney, and lung cancers.

One way metformin works against cancer is by reducing blood glucose levels. Cancer cells often rely on glucose for their energy needs, and by decreasing glucose levels, metformin can inhibit cancer cell proliferation and survival.

Based on this study, metformin was found to activate people's immune response against cancer cells. This action can help improve the body's ability to recognize and attack cancer cells, potentially aiding in the suppression of tumor growth.

Also, combining metformin with intermittent fasting has been shown to have a strong reduction in tumor growth without causing excessive weight loss or toxicity. Intermittent fasting is a dietary approach that involves periods of fasting.

2. It helps with weight loss

Weight loss is another benefit for those who are obese or who have metabolic dysfunction. Obesity occurs when there is an imbalance between energy intake (calories consumed) and energy expenditure (calories burned).

Research shows that metformin contributes to weight reduction by decreasing appetite, reducing calorie absorption from the intestine, and increasing insulin sensitivity. This action can help control food intake and promote weight loss.

In people who don't have diabetes, metformin has been observed to have modest effects on weight loss. While the weight loss may be relatively small, it can still be beneficial, especially when combined with lifestyle changes such as a healthy diet and regular exercise.

3. It reduces the rates of death in people with liver disease

According to research, metformin helps reduce death by 57% in people who already have liver disease. Metformin has potential benefits for people with liver disease. Also, it is safe to use in people with cirrhosis, a late-stage liver disease.

4. It reduces the risk of cardiovascular diseases

Metformin also has some extra benefits for the heart. It improves the "good" cholesterol (high-density lipoprotein) and makes it work better, while also reducing changes in the "bad" cholesterol (low-density lipoprotein).

Also, it helps move cholesterol around in the body and lowers the risk of heart problems.

For people with diabetes, metformin helps the heart muscle work better by improving its energy and metabolism. It also reduces the size of an enlarged heart, which is linked to heart disease.

So, aside from regulating blood sugar, metformin may also help protect the heart and lower the risk of heart problems.

5. It improves kidney function

Acute kidney injury (AKI) and chronic kidney disease (CKD) are two types of kidney problems that can happen quickly or gradually over time. Metformin is beneficial as it can improve kidney function and increase survival rates in people with this condition.

Studies found that taking metformin by mouth every day can help improve the structure and function of the kidneys. It works by activating a signaling pathway, which helps regulate cell growth and energy use in the kidneys.

6. It improves fertility in women with polycystic ovary syndrome (PCOS)

Metformin also helps in stimulating ovulation, encourages regular monthly periods, and lowers the risk of miscarriage in people with polycystic ovary syndrome (PCOS).

Although not yet licensed for treating PCOS, many women with PCOS have insulin resistance. Doctors use it as "off-label" to promote fertility and control the symptoms of PCOS.

Despite the potential benefits of metformin, it is important to note that taking this medication without a doctor’s prescription is not a good idea. Also, metformin, like other medications, has associated risks.

Instead of relying on medications, consider living a healthier life, like eating whole, unprocessed foods and exercising regularly.

Risks of taking metformin when you don’t have diabetes

Off-label uses of metformin may lack sufficient scientific evidence to support their effectiveness and safety. Different people may respond differently to metformin, and not everyone will experience the same effects. 

For example, while some persons may experience weight loss, others may not see significant changes. It's essential to recognize that metformin's effects can vary among individuals.

In countries where prescription medication use is not properly regulated, there is a risk of misusing metformin.

Some people may purchase metformin without a doctor's prescription, often for purposes like weight loss. In such cases, there is a danger of taking it inappropriately, without proper medical supervision. This can increase the risk of adverse effects.

Long-term use of metformin has been associated with a potential risk of vitamin B12 deficiency. This is because metformin can interfere with the absorption of vitamin B12 in the gastrointestinal tract. This may lead to low levels of vitamin B12 over time. Vitamin B12 deficiency can cause symptoms such as:

Although rare, metformin carries a risk of a serious condition called metformin-associated lactic acidosis, which could be a result of a drug overdose. This is a potentially life-threatening buildup of lactic acid in the blood.

However, it's important to note that this risk is relatively low, particularly when metformin is used appropriately and monitored by a healthcare professional.

Taking metformin with other diabetes medications like insulin can cause low blood sugar levels (hypoglycemia). Most health topics tend to focus on high blood sugar levels, but low sugar levels can also be dangerous and potentially life-threatening.

Common side effects of metformin

Here are some common side effects you should look out for if you are taking metformin:

How to know if you need metformin

It is important to note that the decision to use metformin or any medication should be made by a doctor who can determine if metformin is necessary based on a thorough evaluation of your medical history, family history, and the results of your tests.

If you have concerns about your health or suspect you may need metformin, it is important to see a doctor.

Frequently Asked Questions (FAQs)

Can you take metformin when you have prediabetes?

Yes, metformin can be prescribed for individuals with prediabetes. Prediabetes is a condition in which blood sugar levels are higher than normal but not yet high enough to be classified as type 2 diabetes.

Keep in mind that lifestyle modifications, such as adopting a healthy lifestyle, are typically the first-line approach for managing prediabetes. But metformin may be considered in certain cases.

What happens if you stop taking metformin?

If you do not consult your healthcare professional before you stop taking metformin, it can lead to poorly managed blood sugar levels and a potential return of symptoms related to the condition being treated.

Also, abruptly stopping your metformin can lead to withdrawal symptoms marked by symptoms like nausea, headache, and fatigue.

What can you take metformin for?

Metformin is primarily prescribed for the treatment of type 2 diabetes and gestational diabetes. It is also sometimes used off-label for managing symptoms of polycystic ovary syndrome (PCOS) and may have potential benefits in weight management and reducing the risk of certain cardiovascular diseases.


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