Nearly 2,500 years ago, the Greek physician Hippocrates proclaimed “Let food be thy medicine and medicine be thy food” and at the time this was certainly a fundamental truth that all could benefit from adhering to. However as the decades and centuries have passed, and as techniques of farming and plant cultivation have become increasingly the stuff of laboratory experimentation, our “food” is no longer what it was. This is clearly seen in the prevalence of processed chemical laden food that has flooded our supermarkets, however it is also true in areas of food that may not be so apparent – namely the fruits and vegetables that most would assume are natural, unprocessed, and healthy.
To understand how a fruit or vegetable could be less than optimal for abundant health, you first need to understand the nature of plant phytochemicals and how they can assist our bodies. Phytochemicals are secondary plant metabolites that exist as a third tier of nutrient beyond the simple macronutrients (protein, carbohydrate and fat) and micronutrients (vitamins and minerals) already present. These phytochemicals are thought to play a defensive role in the plant against environmental stressors such as pests, disease, radiation, and drought. Interestingly these phytochemicals have been shown to not only aid the plant in question in becoming more robust and impervious to environmental stress, but to also aid those animals that consume the plant and thus ingest these phytochemicals. Examples of these health promoting phytochemicals are resveratrol from grape seed, caretonoids from yellow-orange fruit and veg, and curcumin from turmeric. These phytochemicals have been demonstrated to be effective in reducing the prevalence of many diseases, specifically the big four of the Western world: cancer, cardiovascular disease, diabetes and dementia.
However this is where modern agricultural techniques have let us down. Over the past century, plant breeders in the areas of edible plants have focused their efforts toward producing ever faster growing, plumper, sweeter varieties of most produce. Interestingly, many of the health promoting phytochemicals have bitter or astringent flavour profiles and thus they are bred out of the plants through this process. This selective breeding, along with intensive industrial farming that saturates the soil with unnaturally high levels of growth promoting nutrients such as phosphorous while at the same time destroying all pest and disease stressors through the application of pesticides, fungicides and herbicides, has effectively resulted in nutrient poor varieties of produce which produce extremely low levels of health promoting phytochemicals.
To demonstrate just how depleted these phytonutrients can be, below is a diagram outlining the differences between some heirloom and modern varieties:
Bill Marsh/The New York Times; illustrations by Matt Curtius
It becomes clear that if we are to seriously attempt to maximize our health, we must choose our fruits and vegetables wisely. When shopping look for the more exotic varieties of produce, and don’t shy away from those blemished and slightly insect nibbled apples – they are likely to contain more phytochemicals due to greater exposure to environmental stress than their plump and perfectly waxed cousins.
There is another layer to this issue, and that is the length of time from when produce is harvested to when it arrives on your plate. Most major supermarkets will cold store fruit and vegetables for days or even weeks before you have the chance to purchase them. What many do not know is that this produce is not dead once it is harvested, it continues to respire and pursue its cellular processes, and over time this will deplete the produce of crucial nutrition. As an example: broccoli, kale, and spinach are all highly recommended nutrition dense foods, however within two or three days from harvest they may have half or even less of their original antioxidant levels. Buying local produce at farmers markets is a great way to ensure your produce contains the highest levels of nutrients (apart from growing and harvesting it yourself of course!).
So here are my tips for ensuring the fruits and vegetables you eat contain the highest level of nutrition possible:
- Buy heirloom varieties of fruits and vegetables whenever possible. Swap examples include:
- Swap orange carrots for purple carrots
- Swap large tomatoes for multi coloured heirloom cherry tomatoes
- Swap white potatoes for small fingerling varieties
- Swap iceberg lettuce for rocket, kale and baby spinach
- Eat your produce as soon as possible from purchase, especially broccoli, asparagus, kale and spinach
- Buy you produce from local farmers markets
- Store your produce well. For example, the best way to store leafy greens is to place them in a zip lock back, squeeze out all the air, prick a dozen or so small holes with a pin in either side of the bag, then store in the fridge.
And finally, have a go at growing some of your own produce. Even if you live in a small apartment, a few pots of herbs such as rosemary (full of incredible antioxidants by the way), thyme and basil, along with a small cherry tomato bush, will greatly boost your phytochemical intake and improve your health. If you live in a house with some land, why not reclaim some of that boring lawn and create a raised garden bed. You’ll be amazed at what you can grow yourself. I recommend purchasing heirloom seeds from a website such as Green Harvest and trying your hand at some ‘purple dragon’ carrots or ‘green sprouting calabrese’ broccoli – the flavour of produce you grow yourself can never be beaten!
In wellness
James
