Where do heavy metals in some chocolate come from?
Q: I was disappointed to read that some chocolate bars have high amounts of heavy metals. My particular favorite was high in both lead and cadmium. Can you tell me why? Are there any chocolates that are safe to eat?
A: Consumer Reports published an analysis of popular chocolate brands in a recent issue. Unfortunately, as you note, many were contaminated with lead, others with cadmium and a few with both.
Cadmium comes from the tropical soils in which cacao trees grow. The trees get cadmium along with nutrients and it accumulates in cacao beans as they mature.
The sources of lead contamination seems to be different. Freshly harvested cacao beans don’t have much lead, but as they dry, they accumulate dust. In some environments, the dust is full of lead. According to Consumer Reports, keeping harvested beans off the ground and away from roads and dust will cut down on the lead in chocolate bars.
Consumer Reports identified five “safer” chocolate bars that came in under the maximum allowable dose level for these metals. They are Ghirardelli Intense Dark (both 72% and
86% cacao), Taza Chocolate Deliciously Dark (70%), Mast Dark Chocolate (80%) and Valrhona Abinao (85%).
Q: I have been taking 1,000 milligrams of vitamin C daily. As a result, I believe, I have not had a gout flare-up in over 15 years.
When I used to get a
gout attack, I would boost the dose and add ibuprofen. That resulted in milder pain that only lasted a few days instead of weeks.
A: In 2005, researchers at Johns Hopkins University conducted a placebocontrolled study to find out how taking vitamin C (500 milligrams daily for two months) affected blood uric acid levels (Arthritis and Rheumatism, June 2005). That trial demonstrated that the vitamin supplement significantly lowered this primary risk factor for gout.
The Physicians’ Health Study II collected data from middle-aged male doctors for a decade. An analysis of the information on these 14,641 men shows that those taking vitamin C (500 milligrams/day) were diagnosed with gout at a rate of 8 per 1,000 personyears (American Journal of Clinical Nutrition, Sept. 2, 2022). In comparison, the men on placebo developed gout at rate just over 9 per 1,000 person-years. That may not sound impressive, but it is a 12% relative reduction in the risk of gout.
Q: I have been taking zolpidem for at least ten years.
I have no side effects. I tried getting off but just cannot. I would like to know if there are any long-term consequences I should be aware of.
I’m trying to cut back by using GABA and melatonin. Do you have any other recommendations?
A: Doctors are still debating whether long-term zolpidem (Ambien) use might increase the risk for cognitive difficulties (Experimental Gerontology, July 15, 2020). Falls and fractures might be more of a hazard over the years.
GABA (gamma-aminobutyric acid) and melatonin are both produced in the brain. Drugs that work through GABA don’t appear helpful for insomnia (BMJ, Nov. 18, 2022). A review and meta-analysis of melatonin found that it may be helpful for children and adolescents with insomnia (Sleep Medicine Reviews, December 2022). For adults, however, this supplement was not very effective.