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Berberine Dosage: Is Berberine Better Than Metformin?

Berberine Supplement Berberine, long a staple in Traditional Chinese Medicine, is a supplement derived from golden seal and other plant compounds, that is used for a wide variety of purposes, from gut repair to lowering markers of cardiovascular risk like LDL-C, and even as tool for keeping blood sugar in check. 1 Often mentioned in the same conversation as berberine because of their similar metabolic targets, Metformin, is a popular diabetes drug that lowers blood sugar and blood cholesterol, and that has also shown promise in reducing the risk for certain types of cancers. 2 3 4

Why are biohackers using Metformin?

According to Tim Ferriss, Silicon Valley executives have been taking metformin as a prophylactic measure for cancer prevention and as a longevity strategy. I know a friend or two who takes Metformin in NYC as well. Metformin has been shown to inhibit the mTOR pathway, which “plays a pivotal role in metabolism, growth and proliferation of cancer cells.” Although it isn’t proven, biohackers largely use metformin as an anti0cancer drug. Ironically, there have been several Metformin recalls due to unacceptably high levels of NDMA in many drug samples. For more on the quality control issues with Metformin doses, see the FDA’s page.

Side effects of Metformin

Biohacker and professional trainer, Ben Greenfield believes Metformin harms athletic performance and mitochondrial function over the long term. WebMD lists many side effects of metformin, such as:
  • B12 deficiency
  • Physical weakness
  • Muscle pain
  • Upper respiratory tract infection
So, if the rub in Metformin is that it controls blood sugar swings and aids glucose disposal, but also causes weakness and a general lack of performance, maybe it’s wise to hunt for natural alternatives, especially in light of all the metformin recalls?

Is berberine better than metformin?

Berberine is a natural alkaloid compound long used in Traditional Chinese and Aryuvedic medicine. When taken orally, berberine has a hypoglycemic effect in that it lowers blood sugar.[ footnote id=”5″] In fact, studies show that supplementing with berberine is just as effective at treating type 2 diabetes as metformin and that it also inhibits the mTOR pathway as metformin does. 6 7 Why then wouldn’t berberine act as a buffer against the spiking insulin levels that increase circulating levels of IGF-1 and eventually mTOR? Why isn’t everyone taking a little berberine everyday, especially with high glycemic meals? There are five answers:
  1. As far as cancer is concerned, berberine may behave differently depending on the dose administered
  2. Most people haven’t heard of berberine
  3. Berberine carries with it some unpleasant side effects
  4. Berberine is actually more expensive than metformin which costs only a few dollars a pill

Dosing berberine

When micro dosed, at very small levels, this peer reviewed study published in the Journal PLOS One, found that berberine actually encouraged the growth of cancer cells and interfered with cancer drug therapies:
Our results demonstrated that berberine at low dose range (1.25 ~ 5 μM) promoted cell proliferation to 112% ~170% of the untreated control in various cancer cells, while berberine at high dose rage (10 ~ 80 μM) inhibited cell proliferation. Further, we observed that co-treatment with low dose berberine could significantly attenuate the anticancer activity of chemotherapeutic agents, including fluorouracil (5-FU), camptothecin (CPT), and paclitaxel (TAX).
These findings are known as hormesis, the situation where a low dose can cause adaptation, where a higher dose is destructive. The question becomes: what does a dose that has anti-cancer effect look like in milligrams? 1.25 – 5μM is between 0.42 – 1.68mg of berberine, which is a very very low dose. Even a “micro-dose” regimen at 200mg is far higher than the amount shown to encourage cancer growth and diminish activity of cancer medications. Many supplements offer berberine in 1,000 mg doses.

Side effects and cycling use

When I took berberine, I saw side effects from higher doses at 500 -1,000mg a day. For some people, lower doses may be the way to go, although the studies on diabetes dosed at 500mg a few times a day. Berberine is a plant, but acts like a drug. It will lower blood sugar and can cause dizziness. Another common berberine complaint with higher doses of berberine is upset stomach, which is part of the reason I was taking smaller doses.

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Although the anticancer effect is unclear, it appears that occasional 6-8 week courses of berberine between 100-1,000mg a day are safe. In addition to preventing spikes in blood sugar, using berberine in this way could also prove beneficial to heart health and digestive health for many people. I plan to use berberine for maintaining gut health and occasionally as a hedge against very high glycemic meals.

Dr. Aaron Gardner, BSc, MRes, PhD

Dr. Aaron Gardner, BSc, MRes, PhD is a life-scientist with a strong background in genetics and medical research, and the developing fields of personalized medicine and nutrition. Read his full bio here.

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