Aging is the biggest risk factor for cancer: The older we get, the more likely it is that a tumor becomes malignant — and lethal. But the biology behind this phenomenon is little understood.
A new study, published in Nature, describes a stunning new link between aging and the rapid proliferation of cancer, pinpointing a substance that our bodies naturally produce. The chemical, called methylmalonic acid, is a byproduct of protein and fat metabolism, and levels of this metabolite increase substantially as people age. The study found that high levels of methylmalonic acid, or MMA, boost a tumor’s malignancy — allowing cancer cells to breach new tissues, fight off chemotherapies, and survive.