The “detox” fruit juice craze is here to stay. There is an ever-greater range of this kind of products. But, how much truth is there in it? Can they really help improve our health?


ZFruit juices, smoothies, shakes, and even diets now bear the “detox” or “purifying” label. These terms evoke a sense of well-being in consumers and may even serve to soothe their conscience with respect to summer holiday excesses.

And there is an ever-increasing number of establishments offering this type of product. It is a trend which, like others, is imported from countries where it has been in vogue for some years, thanks in part to the rise of the Internet, sometimes able to amplify health messages that do not always have a solid scientific basis. d

What is a detox product?

The first difficulty we encounter is actually trying to define what a “detox” product is. To be able to make this type of health claims, it is necessary to comply with the regulations. It is the task of the European Food Safety Authority (EFSA) to assess and regulate the effectiveness of dietary supplements, additives, and food components, and, where applicable, to endorse health claims (and detoxification is not among these).

Therefore, within the catchall of “detox” products we find all sorts of shakes, juices or smoothies, usually made from a mixture of fruits and/ or vegetables, and some components declared to be “superfoods”, another category born more out of fashion than objective parameters: ginger, kale, açaí, etc. There are also programs or diets designed to “detoxify and purify” the body, which are more complex, last longer and, of course, cost more.

Do they really work?

It is true that the components of this type of smoothies are, in principle, healthy. But we cannot attribute properties to these food mixes that go beyond their nutritional content. There is nothing in these smoothies, or even diets, that will make it easier for the body to excrete more toxins than it would under normal conditions. It is true that the deficiency of some vitamins, or a low intake of antioxidants, may give rise to imbalances, and to an increase in oxidative stress. However, it is not necessary to turn to this type of “miracle” products to achieve an adequate intake of nutrients. In fact, a diet based on mostly raw foods has been shown to have adverse effects on our health. Failing to cook food hinders the absorption of nutrients, even if we turn to liquefied and shredded foodstuffs.

Another issue associated with detox juices and raw food diets is the question of enzymes. However, given that they are proteins, they are denatured and lose their function when they encounter stomach acids.

Se han identificado riesgos asociados a los zumos «détox» como la alta ingesta de oxalatos

“Intox” juices?

So, if these drinks or beverages, including the diets, do not facilitate the detoxification of the body, what benefit do they provide? Can they be harmful? The answer would seem to be affirmative. Recently the aforementioned EFSA issued a report in which it identified as an emerging risk the high consumption of oxalates derived from the consumption of this type of smoothies. Spinach, kale or, above all, beet, are some of the foods that are habitually included in these mixtures, and which contain large quantities of oxalates. A single glass of these drinks can contain more oxalates that the recommended daily amount.

It is easier to ingest a greater amount of fruit or vegetable in the form of juice, than as whole foods (a challenge the reader can try at home: eat three oranges whole, or drink the juice of the same three oranges). The oxalates are therefore going to be concentrated in that “detox” drink.

An appetizing option?

There is no doubt that the ubiquity of these detox drinks means that, at some point in time, we may be tempted. Moreover, it may be one of the few healthy alternatives when it comes to eating in some establishments. If this is the case, if we simply want to enjoy a refreshing fruit-flavored drink with a certain oriental spicy touch, well that’s fine. But we should not believe that this juice is going to purify our body, ridding it of summer holiday excesses. Learning to eat well and maintaining healthy habits (not dieting) is what is going to facilitate that our antioxidant defenses and our detoxification routes remain “at full gas”.