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Nutrients. 2015 Jan; 7(1): 552–571.  Published online 2014 Jan 14. doi:  10.3390/nu7010552 PMCID: PMC4303853  Dietary Strategies for the Treatment of Cadmium and Lead Toxicity - Qixiao Zhai,1 Arjan Narbad,2 and Wei Chen1,3,*

5. Probiotics as Functional Food Supplements

Probiotics are defined as “live micro-organisms which, when administered in adequate amounts, confer a health benefit on the host” (WHO 2001).

Most commercial probiotics contain species of Bifidobacterium, Bacillus, Lactobacillus as well as the yeast Saccharomyces boulardii.

Probiotics is now a multibillion dollar industry. There is significant number of studies indicating the benefits of probiotics in relation to antibiotic associated diarrhoea, allergy, lactose intolerance, reduction of cholesterol as well as development of immune system and protection against gut pathogens.   

Some species of lactic acid bacteria (LAB) including Lactobacillus rhamnosus, L. plantarum, and Bifidobacterium longum are capable of binding heavy metals in vitro. Moreover, LAB are known to have antioxidative properties in human subjects, which may be another important characteristic for heavy metal toxicity protection. On the basis of these functions, specific LAB have the potential to be developed as probiotics for alleviation and treatment of heavy metal toxicity. This hypothesis was also proposed in a recent review by Monachese et al.  

Our work has demonstrated that two lactobacilli strains exhibit protective effects against Cd and Pb toxicity in mice.

L. plantarum CCFM8610, a probiotic with a good Cd binding capacity, is able to protect mice from acute and chronic Cd toxicity via its intestinal sequestration and antioxidant effects. The oral administration of this strain effectively decreased intestinal Cd absorption, reduced Cd accumulation in tissue, alleviated tissue oxidative stress, reversed hepatic and renal damage, and ameliorated the corresponding histopathological changes of Cd-exposed mice.

L. plantarum CCFM8661 protects against Pb toxicity by recovering the blood ALAD activity, decreasing the Pb levels in the blood and tissues and preventing Pb-induced oxidative stress.

Several recent reports confirmed that other probiotics may also be protective against heavy metal toxicity. A mixture of

• L. rhamnosus Rosell-11,
• L. acidophilus Rosell-52 and
• B. longum Rosell-175

significantly reduced Cd-induced genotoxicity both in vitro using liver tissue culture and in rats.

Another study investigated the potential of L. rhamnosus GR-1 supplemented yogurt to lower heavy metal levels in at-risk populations of pregnant women and in children in Tanzania.
Their results showed that blood levels of mercury and arsenic of pregnant women increased in the control groups (p < 0.05) but remained stable in the probiotic group, indicating a protective effect of L. rhamnosus GR-1 consumption.

This means that with confirmed protection against heavy metal toxicity in animal studies, probiotics also have the potential to prevent or treat heavy metal toxicity in humans. However, it is worth pointing out that the strain L. rhamnosus GR-1 does not significantly reduce blood levels of Pb and Cd in pregnant women or children.

These studies indicate that specific probiotic or cocktails of probiotic mixes may be required for protection against different types of heavy metal toxicity.

Lactobacilli are widely used in the food industry and are generally regarded as safe. The use of these probiotic lactobacilli can be considered a new dietary therapeutic strategy against heavy metal toxicity.