Very Low Calorie Diets

When I began researching the risks of very low calorie and low fat diets, I was surprised at just how common gallstones really are, because of this I thought this should be discussed first.

It has been well documented that weight loss, in particular, rapid weight loss increases your chances of developing new gallstones. In more then one study, it has been shown that new gallstones have formed in as little as only 4 weeks into a VLCD (< 800 cal) [1]. One study claims 25-35% of people who experience rapid weight loss form gallstones after their VLCD diet [2] and another that claims a higher percentage of 54.5% of subjects developing gallstones [3], not very good odds!
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As discussed in the previous article, very low calorie diets can cause gall stones due to rapid weight loss as well as the lack of fat that is commonly seen on this diet. This, may also be a danger for low calorie diets which also commonly results in rapid weight loss, that are very low fat and can easily slip into the VLCD category for some as well.

Liquid Protein diets and Sudden Death

A concern is the sudden deaths associated with the liquid protein shake VLCD diets in the 70s and 80s. Now yes, there was a major issue with the type of protein used but it wasn't the only issue. Of course there have been improvements in the quality and thus safety of these liquid meal replacement diets over the short term (though they still carry lots of risks) BUT they do not show any safety for unsupervised diets, let alone ones that are simply a stab in the dark and offer no real nutritional guidelines and minimums, to avoid risks associated with VLCD dieting and fasting.
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