No scientific evidence supports claims that plant-based food supplements reduce blood sugar to normal levels and cure type 2 diabetes

RECLAMACION
Food supplements get “perfect sugar levels restored” and “help with type 2 [diabetes]”
DETALLES
Inadequate support: No clinical trials are available proving that the advertised food supplements restore blood sugar level to a healthy level or cure type 2 diabetes. While some of their alleged ingredients may help to reduce sugar levels in experimental settings, higher quality evidence, such as large, double-blind, randomized, controlled clinical trials are required if we want to know how they work in people.
ASPECTOS CLAVES
Type 2 diabetes is caused by excessive levels of sugar in the blood, which can lead to serious health problems. At the moment, no cure for type 2 diabetes exists. The best way to prevent the onset of diabetes or keep it under control once it is diagnosed is to consume a healthy balanced diet with moderate amounts of carbohydrates and fat and to adopt a more active lifestyle.

RECLAMACION: Food supplements get “perfect sugar levels restored” and “help with diabetes] type 2” without the need for additional medication.

REVIEW


One in ten Americans suffer from type 2 diabetes. If left unchecked, diabetes can have dire consequences, such as damage to organs, nerves and arteries, or amputation. Diabetes is also among the top ten causes of mortality in the U.S. in 2020. It is therefore a major public health concern.

Diabetes occurs when a person has sustained, excessive blood sugar levels. The threshold for diagnosing someone with diabetes is met when the level of fasting blood sugar is above 126 mg/deciliters (dL); a healthy individual would have a level between 70 mg/dL and 100 mg/dL. The vast majority of people with diabetes have type 2 diabetes. In type 2 diabetes, cells may stop responding to insulin (insulin resistance), the hormone responsible for promoting the movement of sugar from the blood into tissues. The failure of insulin to work properly can lead the pancreas to keep producing more and more insulin in order to bring blood sugar levels down. Over time, the pancreas may become “tired” and produce less and less insulin.

There’s no cure for type 2 diabetes and managing the disease can be challenging. Patients require regular monitoring of blood sugar level and sometimes the use of oral or injectable drugs. People with diabetes are also recommended to adopt a healthy, balanced diet and increase physical activity, as these help to lower blood sugar level by reducing sugar intake and increasing sugar consumption by muscles.

However, several Facebook posts claimed that there is a “life hack” that would restore a “perfect sugar level” without the need for other medication. One example of such a post claimed that this routine would “neutralize sugar” and “help with [diabetes] type 2”. Other posts linked to sites that claimed that high blood sugar had “nothing to do with lifestyle, genetics, meds or expensive treatments”, or that there was a readily available “extremely cheap insulin replacement”.

Such claims may cause diabetic people to stop pursuing a healthier lifestyle and taking their medication and therefore lead to life-threatening consequences. In fact, the U.S. Food and Drug Administration (FDA) issued a warning letter to manufacturers for illegally selling such dietary supplements, arguing that “dietary supplements that make fraudulent claims to treat diabetes are unapproved new drugs that could potentially harm consumers who use these products instead of seeking safe and effective FDA-approved treatments”.

However, these claims are unsupported by clinical evidence and these posts are part of an advertising campaign to get users to buy dietary supplements. Health Feedback previously reported on similar scams, which made bold promises of improved health to sell products that weren’t clinically proven.

These Facebook posts tended to exhibit similar characteristics. The posts would contain links to websites with generic domain names that evoke the idea of wellbeing, such as vigoroushealthyliving.com or vitalizehealthresearch.com. Clicking on the links or images on these websites would lead the user to another page selling products such as “Glucofort”, «Gluzabet» or “Glucotrust”.

However, these websites don’t provide the clinical data supporting the claim that these or similar products effectively normalize blood sugar levels in diabetic patients. Such bold claims should be backed by large-scale, double blind randomized control clinical trials, which are considered the gold standard for evaluating the efficacy of a treatment.

We also analyzed the composition of these products. The page for Glucotrust states that it contains plants such as juniper berry, cinnamon, Gymnema sylvestre, licorice, and other compounds such as biotin and chromium.

Several of these compounds have been used in traditional medicine, such as licorice, which is traditionally used in Europe[1], and Gymnema sylvestre, also known as gurmar, which is used in Ayurvedic medicine[2].

There is scientific data suggesting that some of these plants have an hypoglycemic effect—that is, they reduce the level of blood sugar. However, it’s important to assess the quantity and quality of the scientific data before concluding that these dietary supplements are effective treatments for type 2 diabetes. In fact, as we show below, it appears that clinical results are mostly preliminary and cannot support the claim that a mixture of these plants would cure diabetic patients.

Cinnamon has been associated with reduction of sugar levels in several studies. However, meta-analyses—a type of statistical analysis that combines the results from two or more independent studies—about cinnamon’s benefits concluded that the existing studies were designed in very different ways and the results varied greatly from study to study. This means that the current body of evidence doesn’t provide a reliable answer on whether cinnamon is beneficial for people with diabetes, so more research is still needed to answer this question[3,4].

In fact, some clinical trials actually reported that cinnamon had no effect on blood sugar level[5]. Other clinical trials did report a reduction of blood sugar level among people who took cinnamon, however, their blood sugar level still remained above the threshold for a healthy blood sugar level[6], meaning that patients remained diabetic.

Gymnema sylvestre is another compound that has been associated with hypoglycemic effects. A meta-analysis reported ten clinical trials describing a reduction in blood sugar level after consumption of Gymnema sylvestre[7]. However, only one of them was randomized and double-blind, two of the characteristics expected of a high-quality study. However, this trial didn’t study diabetic patients[8]. The authors of the meta-analysis concluded that “the number of available trials was low to draw any definite conclusion” and that “more RCTs with higher sample sizes are needed to investigate [Gymnema sylvestre’s] effectiveness as a therapeutic agent. Furthermore, the molecular-level mechanism of actions with a standard dose for long-term use of GS should be elucidated”.

A couple of randomized, double blind, controlled clinical trials reported that biotin, also known as vitamin B7, together with chromium helps reduce the level of blood sugar in diabetic patients. However, this reduction was insufficient for reversing diabetes, as the patients’ blood sugar level remained higher than the threshold of 126 mg/dL[9,10]. Furthermore, these patients continued to take oral anti-diabetic drugs. Therefore, the supplementation of biotin and chromium wouldn’t be able to replace medication.

A search on the biomedical literature repository PubMed, run by the U.S. National Library of Medicine, for relevant scientific publications reporting that juniper or licorice altered the blood sugar level in humans returned no results&.

Overall, our findings indicate that more large-scale clinical trials that use designs consistent with each other are needed. Still, even if these clinical trials were to yield positive results, they cannot be directly extrapolated to the Glucofort, Glucotrust, and other similar products. This is because we have no information about exactly how much of each ingredient is present in these products and whether the amount would be enough to produce any effect in people.

In summary, claims that commercially available plant-based products can return blood sugar levels to normal in diabetic patients aren’t supported by any scientific data. While scientific literature reports that some of the listed ingredients may help reduce blood sugar level, the clinical data are very limited and of poor quality. When faced with such claims of miraculous cures, it’s critical to pause and keep in mind the old adage “if something is too good to be true, it probably is”.

NOTES

&: Results obtained from a search on Pubmed using the following queries: (Juniperus communis[Title] OR juniper[Title]) AND (diabetes[Title] OR hyperglycem*[Title] OR hypoglycem*[Title] OR glycem*[Title] OR sugar[Title]) and (Licorice[Title] OR Glycyrrhiza glabra[Title]) AND (diabetes[Title] OR hyperglycem*[Title] OR hypoglycem*[Title] OR glycem*[Title] OR sugar[Title])

UPDATE (27 September 2022):

This review was updated to include a link to the FDA warning letter to manufacturers of fraudulent supplements and highlight the health risks associated with the claims reviewed.

REFERENCES

Publicado: 10 Jun 2022 | Editor:

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