Excessive IGF-1 Growth Hormone: Too Much of a Good Thing

In the Princess Bride (one of my all-time favorite movies!), Andre the Giant played the unforgettable Fezzik. He’s also one of the most famous people to suffer with acromegaly, an excess level of growth hormones such as insulin-like growth factor (IGF-1).

Exactly what its name implies, the protein IGF-1 has an insulin-like structure. Its primary function is to aid growth in children. Once we’re out of our teens, we don’t need nearly as much of it. In fact, over-producing IGF-1 may lead to gigantism.

Another “gigantic” problem with excessive IGF-1? It stimulates the growth of cancer cells. Or, in Dr. Greger’s words:

“When you’re a kid, extra growth can be good; when you’re an adult, extra growth can mean a tumor.”

Yesterday, I wrote about the health risks of eating animal-based protein. In a more recent video, Dr. Greger emphasizes its connection to elevated IGF-1 levels:

“Animal-protein consumption increases the levels of a cancer-promoting growth hormone in the body known as IGF-1, insulin-like growth factor one, which can accelerate the progression of precancerous changes to invasive cancer.”

He continues:

“High blood IGF-1 concentrations are associated with increased risk of breast, prostate, colorectal and lung cancers, potentially explaining the association between dairy milk and prostate cancer risk, for example.”

So, the risk of increased IGF-1 production is just one more reason to avoid animal protein.

But it’s also one more factor in favor of getting your protein from plant-based foods! They don’t increase IGF-1; they actually decrease it!

This NutritionFacts video summarizes the findings of two studies comparing long-term IGF-1 levels in vegans and vegetarians:

“Those eating vegan had significantly lower IGF-1 levels and higher IGF-binding proteins than those just eating vegetarian, suggesting that the more plant-based one’s diet becomes, the lower one’s risk of fueling growth hormone-dependent cancer growth.”

Supporting these studies’ findings is another from Ecuador’s Institute of Endocrinology, Metabolism and Reproduction. For 22 years, the researchers monitored 99 individuals in whom a genetic defect caused IGF-1 deficiency-related dwarfism.

Over more than two decades:

• None died from diabetes.

• None died from cancer.

• One developed a non-malignant tumor.

In the control group, however, 5 percent (1 in 20) died from diabetes and 17 percent (nearly 1 in 6) from cancer.

The scientific evidence seems clear. A low IGF-1 level is related to lowered risks of cancer and diabetes.

And the best way to lower your IGF-1 is to go completely plant based!