A study on over the counter weight loss medications conducted by the University of California (UCLA) found that many of the products contained unlabelled ingredients – namely thyroid hormones. The levels found, in some cases, were not assessed to by insignificant, but in clinical doses which were posed serious health risks to users.
In other words, we’re not talking about some accidental cross contamination in the production process here – we are talking about them being deliberately and illegally added.
The study, which was subsequently presented at the 2015 International Thyroid Congress, tested 29 weight loss supplements available to be bought over-the-counter in the USA. They chose well known popular products which could be purchased in store or online and tested them for thyroxine and tiiodothyronine.
One of the supplements had a daily dose of 66.6 µg of tiiodothyronine. To put that into context, that’s more than someone would be prescribed if they had just had their thyroid removed. So that represents more thyroid hormone than your normal thyroid would typically produce in a day.
It wasn’t just the odd rogue product that contained thyroid hormones. Of the ones containing thyroid hormone (and the report itself is very vague on both the numbers and the brands) those marketed as thermogenics had, on average 19.2 µg/day of triiodothyronine and 29.6 µg of thyroxine. The fat burners had more triiodothyronine – 27.1 µg/day but less thyroxine at 20.7 µg/day.
As one of the co-authors of the study, Dr Leung points out;
“The average consumer should not be expecting to find any thyroid-hormone content in over-the-counter weight-loss products”
These are serious pharmaceuticals designed to treat hypothyroidism and thyroid cancer. There are many potential side effects that could be caused when a healthy individual ingests these drugs – weight loss (which is why they are in these products of course), palpitations, intolerance to heat. With prolonged use, or the doses measured in the study, they could contribute to atrial fibrillation and bone loss.
It’s bad enough in the healthy body but the situation is worse if the unwitting user actually has an underlying undiagnosed thyroid condition. The addition thyroid hormone could cause excesses which lead to thyrotoxicosis.
This is not the first study to focus on this issue. In 2013 a study was published in which the authors had reviewed 10 commercially available thyroid dietary supplements. Nine of the ten products tested contained both thyroxine and tiiodothyronine.
Bad as this is – at least those products were marketed as having a connection to thyroid support. This latest study suggests that thyroid hormones are being routinely added in weigh loss supplements and there is no mention of ‘Thyroid’ anywhere on the labelling and packaging.
Which is altogether more insidious and callous.
Well this is a very good question. This latest study is ultimately pretty useless to us as at no point have they actually identified the rogue brands involved. Presumably this is at the behest of the UCLA legal team, who are scared they would be under siege with lawsuits if the prepetrators were actaully identified.
So they have chickened out and decided to label the entire supplements industry as bad news. This is not very helpful.
We did some research to try and work out how much it would cost to have samples of commercially available fat burners examined in a lab. To help us verify these results and find out who the ‘baddies’ were. Turns out it was quite difficult to find a lab capable/willing to do this. When we did the cost wasn’t prohibitive for a big company ($15K to analyse 20 samples), but was certainly a lot more than a very small website could afford!
The best advice (until these brands are identified) is to stick to well known brands which use cGMP and/or FDA approved manufacturing facilities. And you know the provenance of the product, it should be produced in a country with stringent controls on food / pharmaceutical manufacturing.
In other words, at least ensure they were made in the UK or USA.