Everyone knows about calcium. I don’t think it is really necessary to list why it is so important for human health, but I’ll say it anyway – it is needed to build strong bones, as well as for proper functioning of the heart and muscles. Lack of calcium can even lead to heart failure in the elderly. It also has many other functions, but these are its most important duties. While you can get calcium from milk, leafy green vegetables like kale and collard greens are even better sources.
What isn’t as well known is that calcium can block the absorption of lead, which is very toxic even in small doses. This is yet another reason you should make sure you are getting enough calcium. This is especially important in communities where children are exposed to lead, since it can permanently damage the brain.
According to the Ohio State University Extension Fact Sheet- Human Nutrition and Food Management:
An adequate calcium intake can protect against lead poisoning. It has been observed in animals and humans that both the absorption and retention of lead decreases as calcium intake increases. Many children at risk for exposure to excess lead are also those who live at the poverty level, and may consume a diet with insufficient calcium. Therefore, increasing consumption of low-cost calcium rich foods can reduce the severity of the effects of lead exposure.
Why lead exposure in young children is especially problematic:
Epidemiologic studies of children show that those exposed to lead, even low levels of lead, may have a lower IQ, learning disabilities, behavioral abnormalities and kidney damage. Cognitive and growth defects also may occur in infants whose mothers are exposed to lead during pregnancy. Lead intoxication is a widespread problem. One of every nine children under six years of age has blood lead levels high enough to be at risk. In 1970, an estimated 3 million children aged less than 6 years had blood lead levels associated with adverse health events. Children in older, inner-city neighborhoods are more likely to be affected, but children in suburban and rural areas are at risk too.
There are a lot of ways to ensure you are getting enough calcium, but make food your primary source. While you can get calcium from dairy, vegans or people with lactose intolerance require another source. Luckily, the bioavailability of calcium in kale is even higher than the calcium in milk. It must be noted that while spinach has a lot of calcium, spinach also has a lot of oxalic acid which can block calcium absorption. Therefore, do not rely on spinach or other high oxalic acid foods for calcium(kale is a low oxalic acid vegetable). Oxalic acid also contributes to kidney stones.
Increasingly, many foods and beverages are fortified with calcium, like orange juice and rice milk for example. Also make sure you get enough vitamin D to absorb the calcium. If you have very young children, do all you can to make their environment lead free, besides making sure they get enough calcium. Don’t forget that lead tastes sweet.