TUDCA and Weight Loss: What Human Studies Show

We found no study in people that tested TUDCA for weight loss. In the two small placebo-controlled trials that measured body weight or body fat, neither changed, and the weight loss you may read about online comes from studies in mice. One four-week trial found better insulin sensitivity on TUDCA; a second, unpublished trial did not.

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TUDCA turns up in weight-loss forums alongside claims that it melts fat, boosts metabolism and works like the new weight-loss injections. The research behind those claims is mostly in mice, some of them given TUDCA by injection, and the human studies tell a quieter story.

This guide sets out what the studies in people measured: body weight, body fat, insulin sensitivity, liver fat and cholesterol. It explains why mouse results don't carry over, and what is known to help with weight.

Does TUDCA Help You Lose Weight?

We found no study in people that tested TUDCA for weight loss. Two small placebo-controlled trials, both mainly about insulin sensitivity, also measured weight or body fat, and in both, neither changed:

Trial	Who took part	TUDCA dose and length	Weight and body fat	Insulin sensitivity
Kars 2010 [1]	20 adults with obesity and insulin resistance	1,750 mg a day, 4 weeks	No change: 100 kg before and after on TUDCA; body fat 39% before and after	Rose about 30% in the liver and muscle on TUDCA, not on placebo; no change in fat tissue
Registered trial, NCT01877551 [2]	27 adults with HIV on protease-inhibitor medicines	1,750 mg a day, 30 days	Body fat 35.7% before and after on TUDCA (32.6% to 31.7% on placebo)	No improvement on TUDCA

The second trial's results were posted on ClinicalTrials.gov but, as far as we found, never published in a journal, and it enrolled fewer people than planned [2]. Both trials were short and small, so they can't rule out an effect over months. What they show is that weight loss wasn't seen in the only placebo-controlled trials that measured it.

Where Do the TUDCA Weight-Loss Claims Come From?

Most of the weight-loss claims online trace back to studies in mice. In one widely cited study, mice on a high-fat diet were given TUDCA by injection for 15 days [3]. Results in mice often don't carry over to people: the doses differ, and an injection reaches the body differently from a capsule. A headline that says TUDCA "reduced body fat" can leave out that the bodies were mice.

The same applies to claims that TUDCA acts like a GLP-1 weight-loss drug. They rest on laboratory findings: in immune cells and mice, TUDCA switched on TGR5, a receptor that responds to bile acids, and in pancreas cells taken from mice it boosted insulin release [4, 5]. We found no study in people that measured GLP-1, the hormone those drugs mimic, on TUDCA [1]. Our guide to TUDCA and GLP-1 drugs covers the gallbladder questions those medicines raise.

Does TUDCA Improve Insulin Resistance?

The evidence in people is split. In the 2010 trial, 20 adults with obesity took TUDCA or placebo for four weeks, and insulin sensitivity in the liver and muscle rose about 30% on TUDCA and not on placebo; fat tissue didn't improve [1]. Simpler blood tests, such as fasting glucose, didn't change significantly [1]. In the second trial, in people with HIV whose medicines can cause insulin resistance, TUDCA did not improve insulin sensitivity over 30 days [2].

How was insulin sensitivity measured?

Both trials used an insulin clamp, a detailed hospital test. Insulin is given through a drip at a steady rate while glucose is added to keep blood sugar normal; the more glucose the body needs, the more sensitive it is to insulin. In the 2010 trial, tracers also showed how much of the effect was in the liver and how much in muscle [1].

What about type 2 diabetes?

Neither trial was in people with type 2 diabetes. One small type 2 diabetes trial of TUDCA was completed with no results posted [6]. In healthy adults, a single dose of TUDCA before a sugary drink didn't change blood glucose or insulin afterward [7]. If you have diabetes, TUDCA is not a substitute for your treatment.

Does TUDCA Lower Cholesterol?

We found no trial in people designed to test TUDCA for blood cholesterol. In one study of 24 people with primary biliary cholangitis, a liver disease, total and HDL cholesterol both fell at the two higher doses over six months, with no placebo group [8]. HDL is the "good" cholesterol, so that isn't the change people usually hope for. In a small unblinded study after liver transplant, cholesterol was lower in the early months on TUDCA [9].

Other findings concern cholesterol somewhere other than the blood. In six healthy men, the share of cholesterol absorbed from food fell while they took TUDCA or UDCA [10], and in people with gallstones, TUDCA made bile less saturated with cholesterol [11]. Our guide to TUDCA and gallstones covers the bile studies.

Does TUDCA Reduce Liver Fat?

In the 2010 trial, liver fat didn't change over four weeks on TUDCA or placebo [1], and no study has tested TUDCA as a treatment for fatty liver. Losing weight is what lowers liver fat: by NIDDK's figures, losing 3 to 5% of your body weight can reduce it [12]. Our guide to TUDCA for liver health covers the liver studies.

What Does Help With Weight Loss?

The approaches with evidence behind them are changes to what and how much you eat, more physical activity, and, for some people, a weight-loss medicine your doctor may prescribe [13, 14]. Weight lost at 1 to 2 pounds a week is more likely to stay off [15], and losing weight at a slow pace may make gallstones less likely: NIDDK says experts recommend losing 5 to 10% of your starting weight over six months [16].

Can You Take TUDCA With Diabetes Medicines?

We found no interaction study in people of TUDCA with metformin or other diabetes medicines, and the TUDCA medicine labels don't name them [17]. In a 12-month type 1 diabetes trial whose results are posted only on a registry, people took TUDCA alongside insulin and no side effects were reported in either group, but the trial wasn't designed to test interactions [18]. If you take medicine for diabetes, ask your prescriber or pharmacist before adding TUDCA. Our guide to who should not take TUDCA lists the medicines the labels do name.

What About Weight After Gallbladder Removal?

Some people gain weight after gallbladder removal, but studies disagree and none shows that the surgery itself causes weight gain. In one small study, body mass index rose by an average of 1.8 after the operation [19]; in another, which compared people with a group who didn't have surgery, it didn't rise over six months [20]. Our guide to weight gain after gallbladder removal sets out the studies.

After removal, bile flows directly from the liver into the small intestine instead of being stored for meals [21]. Dr.Primal's TUDCA is made for life after gallbladder removal and taken with meals, to support healthy bile flow and fat digestion when richer meals feel heavy. It is not a weight-loss product.

In Summary: TUDCA and Weight Loss

No study in people has tested TUDCA for weight loss, and in the two small trials that measured them, weight and body fat didn't change. One four-week trial found better insulin sensitivity on TUDCA and a second found none, and no trial in people has been designed to test it for cholesterol. The weight-loss results online come from mice.

If you are working out what is behind your symptoms after meals, our digestion quiz is a quick way to put your symptoms and habits in order.

This article is for general education and is not a substitute for advice from your doctor. TUDCA is sold as a dietary supplement. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.