Colorful fruits and vegetables may be a clue about their nutrition
Colorful fruits and vegetables may be a clue about their nutrition

By Susan Elrod, PhD

Many consumers are interested in the content of polyphenols, the wonderful antioxidants suggested to improve health, in their favorite foods.  The good news if you love elderberries and other dark fruits is that, in general, the stronger the color of the food, the more polyphenols (or other phytochemicals).1Literally, chemicals in plants (fruits and vegetables in this case). Some phytochemicals, like beta-carotene in carrots, are not polyphenols but still impart color to the plant.   This makes sense: it is these very compounds that give these foods their color.  The beautiful deep color of elderberries is due to a set of compounds known as anthocyanins;2Wu, H., et al. Determination of anthocyanins and total polyphenols in a variety of elderberry juices by UPLC-MC/MC and other methods. Acta Hortic 2015; 1061:43-51. these compounds make fruits and vegetables red, blue, or purple, depending on their structure.  Elderberries have been studied for various potential health benefits, including anti-inflammatory effects3Farrell, N., et al. Anthocyanin-rich back elderberry extract improves markers of HDL function and reduces aortic cholesterol in hyperlipidemic mice. Food Funct 2015; 6:1278-1287. Farrell, N., et al. Black elderberry extract , and it is hypothesized that such potential benefit may be due to the high amount of polyphenols in elderberry, particularly anthocyanins. 

That stated, studies have also shown the possibility of significant variation in the phenolic and anthocyanin content according to the type of elderberries and where and when they were grown1.  This means that it may not be possible to predict the amount of polyphenols you’re consuming in your fruits.  However, you can still be confident that brightly-colored fruits and vegetables will likely have significant amounts of polyphenols, and fruits like elderberries will primarily contain anthocyanins.

So what are anthocyanins, anyway?  And what can they do for you?

Anthocyanins are a specific type of polyphenol; you’ll often hear them grouped with anthocyanidins.  The reason for this is that anthocyanins are just anthocyanidins with a sugar group added.  So then what are anthocyanidins?  They have the following basic structure:

The name of the anthocyanin will be based on what molecules are attached to each point labeled “R.”  For our purposes, you don’t need to understand the differences between these molecules or compounds; the important thing here is that a lot of those R-groups will have oxygen, which reacts with free radicals in our body to protect against a lot of damage.  The specific anthocyanins/anthocyanidins in elderberries include delphinidin, cyanindin, peonidin, and pelargonidin1.  These compounds have been studied for potential health benefits, particularly for prevention of certain cancers,4Thomasset, S,. et al. Do anthocyanins, cancer chemopreventive pigments in the diet, merit development as potential drugs? Cancer Chemother Pharmacol 2009; 64:201-211. cardiovascular disease,5 Dayoub, O., et al. Pleiotropic beneficial effects of epigallocatechin gallate, quercetin, and delphinidin on cardiovascular diseases associated with endothelial dysfunction. Cardiovasc Hematol Agents Med Chem 2013; 11:249-264. and osteoarthritis.6Haseeb, A., et al. Delphinidin inhibits IL-1β-induced activation of NF-κB by modulating the phosphorylation of IRAK-1(Ser376) in human articular chondrocytes. Rheumatology (Oxford) 2013; 52:998-1008. Nothing has been proven, but these compounds found in elderberries and other fruits and vegetables, to varying extents, are especially beneficial in health and the prevention of certain chronic diseases.  But even with all the evidence regarding the potential health benefits of anthocyanins, these compounds have not necessarily been proven to be better for you than other polyphenols. 

Most polyphenolic phytochemicals have been studied for the prevention of chronic disease and other health benefits.  A lot of that is due to the inherent antioxidant properties of polyphenols, but there have been other mechanisms suggested for polyphenolic benefits besides antioxidant effects. That’s why it’s generally recommended that we not only increase our fruit and vegetable intake but that we consume a variety of fruits and vegetables.  According to the World Health Organization, “… fruits and vegetables are rich sources of vitamins and minerals, dietary fiber and a host of beneficial non-nutrient substances including plant sterols, flavonoids, and other antioxidants and consuming a variety of fruits and vegetables help to ensure an adequate intake of many of these essential nutrients.”7http://www.who.int/elena/titles/fruit_vegetables_ncds/en/ So while you shouldn’t put all your polyphenolic eggs in the anthocyanin basket (so to speak), if you are interested in increasing your anthocyanin intake, those dark purple elderberries are an excellent source.

How about the polyphenol content of processed snacks made with fruits and vegetables?  There has been some limited research done on those fruit and vegetable chips you’ll find in the health food section of your grocery store.  Again, these studies are limited, but it appears chips made from red or purple potatoes (which, in their raw form, will also be high in anthocyanins!)8Harborne, J. B., Plant polyphenols. 1. Anthocyanin production in the cultivated potato. Biochem J 1960; 74:262-269.  do have reasonable polyphenolic and anthocyanin content, though these compounds decrease dramatically in the final product due to the cooking and frying process.9Nemś, A., et al. Anthocyanin and antioxidant activity of snacks with coloured potato. Food Chem 2015; 175:175-182.   So while those colorful veggie chips might be a better alternative to your usual potato chips, a lot of the polyphenols may have disappeared during preparation.  Plus you have to balance that polyphenolic content against increased fat and salt in such prepared foods.  Another study looking at fruit and vegetable chips found that snacks made from chokeberries and blackcurrants, which are dark in color like elderberries, had higher phenolic content and free radical scavenging ability than chips made from apples or carrots.10Gramza-Michałowska, A. & Człapka-Matyasik, M. Evaluation of the antiradical potential of fruit and vegetable snacks. Acta Sci Pol Technol Aliment 2011; 10:63-72.   Still, both these studies reported dramatically lower phenolic and anthocyanin values than that measured for raw elderberries.11Duymus, H. G., et al. In vitro antioxidant properties and anthocyanin compositions of elderberry extracts. Food Chem 2014; 115:112-119.

Related article: INTRO TO ELDERBERRY POLYPHENOLS

1 Literally, chemicals in plants (fruits and vegetables in this case). Some phytochemicals, like beta-carotene in carrots, are not polyphenols but still impart color to the plant.
2 Wu, H., et al. Determination of anthocyanins and total polyphenols in a variety of elderberry juices by UPLC-MC/MC and other methods. Acta Hortic 2015; 1061:43-51.
3 Farrell, N., et al. Anthocyanin-rich back elderberry extract improves markers of HDL function and reduces aortic cholesterol in hyperlipidemic mice. Food Funct 2015; 6:1278-1287. Farrell, N., et al. Black elderberry extract attenuates inflammation and metabolic dysfunction in diet-induced obese mice. Br J Nutr 2015; 114:1123-1131.
4 Thomasset, S,. et al. Do anthocyanins, cancer chemopreventive pigments in the diet, merit development as potential drugs? Cancer Chemother Pharmacol 2009; 64:201-211.
5 Dayoub, O., et al. Pleiotropic beneficial effects of epigallocatechin gallate, quercetin, and delphinidin on cardiovascular diseases associated with endothelial dysfunction. Cardiovasc Hematol Agents Med Chem 2013; 11:249-264.
6 Haseeb, A., et al. Delphinidin inhibits IL-1β-induced activation of NF-κB by modulating the phosphorylation of IRAK-1(Ser376) in human articular chondrocytes. Rheumatology (Oxford) 2013; 52:998-1008.
7 http://www.who.int/elena/titles/fruit_vegetables_ncds/en/
8 Harborne, J. B., Plant polyphenols. 1. Anthocyanin production in the cultivated potato. Biochem J 1960; 74:262-269.
9 Nemś, A., et al. Anthocyanin and antioxidant activity of snacks with coloured potato. Food Chem 2015; 175:175-182.
10 Gramza-Michałowska, A. & Człapka-Matyasik, M. Evaluation of the antiradical potential of fruit and vegetable snacks. Acta Sci Pol Technol Aliment 2011; 10:63-72.
11 Duymus, H. G., et al. In vitro antioxidant properties and anthocyanin compositions of elderberry extracts. Food Chem 2014; 115:112-119.