Definition: "An ergogenic aid is any substance or phenomenon that enhances performance "
Prunes boost IGF-1 levels in humans
Looking for a carbohydrate-rich pre-workout snack? But not so keen on all those products that are bursting with refined sugars? How about dried plums? They are packed with fibre, iron, vitamin K - and researchers at Oklahoma State University discovered that prunes boost your IGF-1 level.
Plums & IGF-1
The researchers wanted to know whether dried plums can help prevent osteoporosis. Plums contain selenium and boron, trace elements that are needed for the synthesis of bone tissue. They also contain the phenols neochlorogenic acid [structural formula shown below left] and chlorogenic acid [structural formula below right].
Dried plums' components mean they also have a high oxygen radical absorbance capacity, which in turn means that people who eat dried plums have fewer free radicals in their blood. Free radicals boost bone decay.
In 1999 the researchers published an abstract about an animal study in which dried plums had increased the bone mass in rats. [J Bone Miner Res 1999; 14:S394.] The study was interesting, because the rats no longer produced estradiol. When the study started their bone mass had already started to decrease.
One hundred grams dried plums contain about 240 kcal, derived mainly from glucose and fructose, but also sorbitol, which is less easily digested. One hundred grams dried plums contain about 15 g sorbitol. If you are sensitive to sorbitol, this is a dose that can have a laxative effect. But for most people, sorbitol only starts to have a laxative effect with an intake of 22-30 g. The researchers only lost one subject because of this problem.
A control group ate dried apples.
What's more, the IGF-1 concentration rose by 17 percent in the experimental group. IGF-1 has an anabolic effect in bone tissue, but also in muscle tissue.
Arjmandi's research was funded by the California Dried Plum Board. [californiaprunes.org]