Solving the Diet-Cancer Mystery:
Scientific Studies Provide Clues
Laboratory: In Vitro Studies
In vitro studies are performed in test tubes. These studies help researchers figure out precisely how and why certain foods or food substances might protect against cancer. Seeking clues as to the mysterious array of chain reactions that happen after we consume a particular nutrient, they examine animal or human cells or tissues removed from the body.
An epidemiological study can suggest that eating green beans protects against cancer. But that’s only an association. With in vitro studies, scientists can look at the chain of events that happens when nutrients and cancer cells meet.
Put those two types of studies together, and you’re closer to solving the mystery than with either type of study alone.
Strengths of In Vitro Studies
In vitro studies are tightly focused, which means that scientists can control for many confounding variables. Once an in vitro study finds a “suspect”– a biological mechanism that might protect against or add to your risk of cancer researchers can then easily test their suspicions in an animal model.
Weaknesses of In Vitro Studies
In vitro studies can’t tell us if an anti-cancer effect that happens at the cell level also occurs in the “real world” of the complex human body. They also can’t tell us how much we might have to eat to reap anti-cancer benefits, and they can only involve food components, not whole foods. You can’t feed a cell an apple.
Now let’s look at the next type of laboratory study: In Vivo