Thursday, May 31, 2012

Teeny Tiny Cranberries

Species name: Vaccinium oxycoccus (=Vaccinium microcarpum)

Common name: Northern cranberry, common cranberry, small cranberry

Location: Alaska (3rd picture from Wikipedia)

The saying "everything's bigger in Alaska" only seems to work for vegetables and mosquitoes. When it comes to other plants, they're considerably smaller due to the harsh growing conditions that they experience during the winter. Spruce trees that would normally grow to be about 50 feet tall within 100 years in the southern part of Canada might take up to 300 years to reach the same size in Alaska. The same can be said about cranberries, which are usually shrubby perennials (meaning they can live for many years). In Alaska, it is predominantly Small Cranberry that grows there (you can probably guess how it gets its common name), but even that doesn't begin to describe its size. Each one of those leaves is only about 0.5-1 cm long, and the fruit are about the same size. Anyone who's ever made their own cranberry sauce before at Thanksgiving or Christmas knows that's a pretty small cranberry!

There are three different species of cranberry, all of which are native to arctic environments around the world. The most economically important species of cranberry in North America, Vaccinium macrocarpon, is native to eastern North America, while the species pictured above is native to North America, northern Europe and northern Asia. Many pieces of literature also consider a third, separate species of cranberry that's native to Europe but I have indicated here that they are the same species (DNA sequencing suggests V. oxycoccus and V. microcarpum are the same species despite having slight morphological differences).

There are many health benefits that cranberries claim to have, but in general it's best to eat them because they taste good, not because they might help fight cancer. There has been the suggestion for many years that cranberries have very high antioxidant levels (which they do; some of the highest of any fruit regularly consumed in a North American diet), and a high level of oxygen radical absorbance capacity or ORAC. Oxygen radicals are a necessity of life if you're an animal, plant or fungus; there is no way not to produce them since they're a byproduct of energy production in cells. Despite this, oxygen radicals have the ability to mutate DNA and a very high oxygen radical stress on the body can lead to tumor formation. Unfortunately, foods with a high ORAC score have so far failed in any scientific trial to translate that ability into something that's biologically relevant. In other words, just because a cranberry has the potential to buffer the effects of oxygen radicals on the body doesn't mean that it actually does. If you're spending all of your disposable income on antioxidant extracts from various plants it's probably best to find something else to spend your money on until there is some solid scientific evidence that any of these supplements (or foods!) have an effect on the body that's tangible.