When it comes to food, calcium has been shown to help prevent cancer and reduce inflammation, but there are some big caveats.
So far, the evidence suggests that calcium is a major factor in cancer prevention, but some research has found it’s also linked to other health problems, including cardiovascular disease.
But some scientists aren’t convinced, citing conflicting results.
“I’m not sure it’s really worth taking a whole lot of that calcium,” says Dr. Jonathan D. Schatz, an epidemiologist and director of the Center for Research on Cancers and Stroke at the University of North Carolina.
“It’s certainly not good for the overall health of your body.”
“It’s good for calcium absorption,” says Marcia Hausmann, a cancer specialist at the Children’s Hospital at Montefiore.
“But I don’t think we should be taking so much of it that we’re basically poisoning our body.
So, yeah, I think it’s a bit controversial.”
The most recent evidence comes from a study published in Nature Communications in 2017, which examined the effects of eating a calcium-rich diet on markers of inflammation in mice.
Researchers found that calcium-dosed mice were less sensitive to infection, which means they’re more likely to be infected by pathogens.
The calcium in the food also helped prevent tumors.
“It does not seem to be the main thing that protects the mouse,” Schatz says.
“So if you have the calcium, you don’t get any cancer.”
But the researchers did find a small but significant increase in tumor incidence in the mice that consumed the calcium-based diet.
The researchers suggest the increased tumor risk may have come from an increase in inflammation.
“The researchers did not find any evidence of a causal relationship between inflammation and tumor growth,” the study authors wrote.
“In other words, the mice may have been less sensitive because of a different inflammatory response to the calcium in their diet.”
In general, researchers say, there’s no evidence to suggest that the diet promotes cancer.
And studies looking at other types of foods that are rich in calcium, such as cheese and eggs, have shown that they are effective in preventing and treating some types of cancer.
However, a few researchers think there’s a big problem with the research.
“One of the reasons we’re not seeing the benefits of a high-calcium diet is because there’s not much of that,” says Schatz.
“What we’re finding is there are a lot of things that can cause inflammation that don’t seem to have any effect on cancer.”
Schatz’s team has found that the calcium content in foods can be very different from one person to the next.
For example, some people have a much higher intake of calcium than others, but their levels are also similar.
The difference in dietary calcium intake is not something that can be measured, he says.
And Schatz points out that the data from the current study is not conclusive, and there are plenty of confounding factors.
“If you’re going to do randomized controlled trials, it’s going to be a lot harder to prove that there’s an effect,” he says, “and you’re not going to see that sort of benefit, if you’re using the calcium from a whole food.”
Another important caveat to consider when it comes the safety of calcium supplements is that many foods have added minerals.
So if you take a calcium supplement that contains added minerals like calcium carbonate, the minerals may not be absorbed into the body as effectively.
The bottom line, says Schutz, is that calcium supplements don’t always appear to be as effective as calcium-containing foods.
“In general,” he adds, “I don’t recommend taking a calcium product unless it’s fortified with calcium.”
The Bottom LineOn this week’s episode of the Food Talk podcast, we talk with the author of a book called The Good, The Bad, and the Ugly about how we can eat more good and less bad, with a focus on food.
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