Why Metformin Isn’t the Anti-Aging Miracle You Might Think It Is

Hack Your Longevity and Age Backwards_NAD+


  • Metformin is a medicine that doctors prescribe to help control blood sugar in diabetic and sometimes pre-diabetic patients
  • Metformin acts on AMPK, an enzyme that tells your cells when they should take in sugar from your bloodstream for energy
  • Research has shown that metformin extends the lives of mice and other animals in a laboratory setting, so people without diabetes have been taking it for longevity purposes
  • People have also used metformin for off-label purposes like treating PCOS, to reduce risk of heart disease, and to prevent cancer
  • Here’s why it may not be the miracle pill you think it is


When I was in my 30s, I found myself at a table with a biotech group that was doing anti-aging research with a diabetes drug called metformin. When I told them that I had been taking metformin, they looked at each other, leaned in, and asked me, “How old are you?”

I told them I was 64.

You should have seen the shocked glances they shot between each other. I kept the prank running long enough to get a laugh out of it, but not long enough to ruin anyone’s day.

Would metformin make me look 30-something in my sixties? I don’t know, I’m not there yet. Metformin has shown some potential for longevity in lots of studies, but there are some drawbacks. Here’s what you need to know about metformin.

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What is metformin?

moringa benefits lowers blood sugar diabetesMetformin is a medicine that doctors prescribe to help control blood sugar in diabetic and sometimes pre-diabetic patients.[ref url=”https://www.nejm.org/doi/full/10.1056/NEJM199602293340906″][ref url=”https://jamanetwork.com/journals/jama/article-abstract/2612613″] It is the most commonly prescribed medicine for blood glucose control.[ref url=”https://www.ncbi.nlm.nih.gov/pubmed/25943187″]

Metformin acts on your mitochondria,[ref url=”https://www.ncbi.nlm.nih.gov/pubmed/23835523″] the power plants of your cells, as well as AMPK, an enzyme that tells your cells when they should take in sugar from your bloodstream for energy.[ref url=”https://www.jci.org/articles/view/13505″]

People have also used metformin for off-label purposes like treating PCOS, to reduce risk of heart disease,[ref url=”https://www.ncbi.nlm.nih.gov/pubmed/12364443″][ref url=”https://www.ncbi.nlm.nih.gov/pubmed/26251408″] and to prevent cancer.[ref url=”https://www.ncbi.nlm.nih.gov/pubmed/22847511″][ref url=”https://www.ncbi.nlm.nih.gov/pubmed/23055147″]

Metformin for longevity

The Science Behind NAD+ Supplements and Aging_Levels of NAD+ and agingMetformin became a popular Silicon Valley drug because of its anti-aging potential. It increased the lifespan of mice[ref url=”https://www.nature.com/articles/ncomms3192″][ref url=”https://www.tandfonline.com/doi/abs/10.4161/cc.7.17.6625″] and bacteria[ref url=”https://www.sciencedirect.com/science/article/pii/S0092867413002675″] in laboratory studies, through multiple actions but mainly because of its effect on AMPK.[ref url=”https://link.springer.com/chapter/10.1007/978-3-319-43589-3_10″]

The downside of metformin

I took metformin for about three years.

I later found out that metformin permanently alters your ability to absorb vitamin B12. Since B12 protects against dementia, helps your immune system, regenerates cells, protects your arteries, and is vital to your brain function, I stopped taking it. I already have the MTHFR gene mutation which interferes with my ability to absorb B12, so I don’t need to stack it on top of that.

Another study found another downside of metformin. While it’s in your system, you don’t get any benefit from the exercise you’re doing,[ref url=”https://onlinelibrary.wiley.com/doi/full/10.1111/acel.12880″] and who wants to put in the work for no reward?

If you’re going to take metformin:

  • Add a high-quality B12 supplement in the methylated form
  • Don’t take it every day. Two or three times a week is enough

To control your blood sugar without metformin

Couple preparing dinnerAll of the benefits of metformin come down to glucose (blood sugar) control. There are better ways to keep your blood sugar steady throughout the day.

Gynostemma. Gynostemma is an herb that you’ll find in capsules and in a lot of longevity tea formulas. Its effects on AMPK are similar to metformin’s effects on AMPK, but some studies show that it drops your blood pressure too low, among other downsides.

RELATED: Reverse Insulin Resistance with Intermittent Fasting

Swear off sugar. Cutting sugar is hard for two or three days, max. After that, you won’t miss it at all. That doesn’t mean you have to shun sweets — here are Bulletproof-approved alternative sweeteners that won’t put you on the blood sugar rollercoaster for the rest of the day.

Eat low-carb, high-fat. Keeping your carbs low encourages your body to adapt to burning fat for energy. When you go low-carb, your body starts producing ketones that you can use for energy. When your body gets used to switching between sugar and fat for fuel, you’re less likely to experience blood sugar spikes and dips, and the carb cravings and crashes that come with them. Here’s how to get started.

Intermittent fast a few days a week or more. Intermittent fasting involves giving your body a break from digestion for a period, usually between 12-20 hours. The most common intermittent fasting schedule is 16-8, where you fast for 16 hours and eat all of your calories for the day in an eight-hour window. When you intermittent fast, your body runs on ketones instead of sugar for at least part of the day. It’s easier than it sounds — you’re sleeping through most of your fasting period! Read this guide and decide what schedule fits your life.





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