Many of us are partial to a bit of chocolate every now and then. And while it is tasty, we know that it is not the healthiest snack we can eat due to its sugar content.
However, new research has shown that it could come with some other unexpected health risks.
A study from The George Washington University in the US, revealed that a concerning amount of cocoa-based products contain heavy metals that exceed what is considered safe.
As part of the research a team analysed 72 consumer cocoa products, including dark chocolate, every other year over an eight year period.
They tested the products for contamination with lead, cadmium, and arsenic, heavy metals that pose a significant health hazard in sufficient amounts.
As much as 43 percent of the products exceeded the maximum allowable dose level for lead.
While 35 percent of the products studied exceeded the maximum allowable dose level for cadmium.
However, none of the products exceeded the maximum allowable dose level for arsenic.
A finding that surprised researchers was the fact that organic labelled products showed higher levels of both lead and cadmium compared to non-organic products.
In line with the results, the team urged people not to consume cocoa products in large amounts.
Leigh Frame, director of integrative medicine at the university, explained: “We all love chocolate but it’s important to indulge with moderation as with other foods that contain heavy metals including large fish like tuna and unwashed brown rice.
“While it’s not practical to avoid heavy metals in your food entirely, you must be cautious of what you are eating and how much.”
But it was noted by study authors that for the average consumer, consuming a single serving of these cocoa products may not pose significant health risks based on the median concentrations found.
However, consuming multiple servings or combining consumption with other sources of heavy metals could lead to exposures that exceed the maximum allowable dose level, the team said.
According to the World Health Organisation (WHO), exposure to lead can cause permanent damage to the brain and nervous system, especially in children.
Lead also causes long-term harm in adults, including increased risk of high blood pressure, cardiovascular problems and kidney damage.
High levels of exposure for children can result in severe damage even causing coma, convulsions and death.
Cadmium is known to have a toxic effect on the kidney, the skeletal system and the respiratory system and is classified as a human carcinogen, meaning it has the potential to cause cancer.
The findings are set to be published in the Frontiers in Nutrition journal on July 31.