In this blog series, we ask Dr. Fogarty, a nutrition and exercise expert from the UK, to weigh in on the science behind how eating a vegetable-based rainbow diet can help you live a longer, healthier life.
Mark Fogarty earned a Ph.D. in Exercise Physiology and Biochemistry at the University of Ulster in the United Kingdom where he has been researching, publishing and lecturing on natural nutritional intervention in the context of exercise stress for over a decade.
Spinaca Farms: In our last article, you talk about what you call ‘The Rainbow Diet‘—a simple rule of thumb to ensure we all get enough antioxidants in our diet to keep free radicals at bay. Can you unpack that for us a little bit? Specifically, what exactly are radicals and where do they come from?
Dr. Fogarty: This is a corker of a question!
Most people know about antioxidants but, what they are “anti” against is perhaps less well known. Buckle in, here we go.
In the mid-1950’s a truly brilliant Scientist proposed the “free radical theory of aging”—also sometimes referred to as the oxygen paradox—that says, “That which gives us life also takes it” (I think I may have invented that saying just now ;).
So, let’s talk about oxygen. Oxygen is an unstable gas and our body takes advantage of that instability to produce energy. Part of the process of energy production involves disrupting electrons and spinning them through the little batteries in our cells called the mitochondria. Most of these reactions are very well controlled but sometimes some of the electrons escape. This is when the trouble begins.
Most molecules have an even number of electrons in their chemical orbit—usually, they exist in pairs. This gives the molecule stability. Sometimes a molecule can lose or gain an extra electron thus making it unstable—a free radical. When oxygen loses one of its electrons it forms the free radical superoxide and, like everything in nature, superoxide seeks balance and it does so by stealing an electron from nearby biomolecular structures such as the lipid membrane that surrounds our cells, perhaps a protein structure or even our DNA. When the electron gets stolen superoxide becomes stable again, but the element it was stolen from is now unstable. This causes a bit of domino effect, if you will, with each element in the chain going through a cycle of losing its electron then trying to find another one which causes subsequent damage along the way.
This is where our antioxidants come in. Antioxidants are simple structures that will willingly give up their electrons without causing too much damage further down the line. For example, the structure that surrounds each of our cells is flooded with vitamin E so when superoxide interacts with lipid cells’ membranes the domino can go around the cell until it meets the vitamin which will donate an electron and stop the chain reaction.
Vitamin E then becomes a radical in its own right, but vitamin C saves the day here and recycles the vitamin E radical back to vitamin C. Now the vitamin C radical is quite sable and doesn’t do much harm after that. This just gives you a little bit of an idea how complex these relationships are.
What is all this got to do with aging? I hear you say. Well, a lot of the damage caused by some of the radicals is repairable, but some of it isn’t and so this damage builds up and contributes to the aging process, cell by cell, day by day, year by year. Although we have a very complex defense system radicals are always in a very slight positive state so there never enough antioxidants to stop all the damage all of the time no matter how much we eat, but we can hopefully slow aging down by making sure we eat a good healthy balanced rainbow.
Spinaca Farms: Give us some examples of some of the most antioxidant-rich fruits and vegetables and the various vitamins they contain so we can add them to our grocery list?
Dr. Fogarty: I have done a lot of work with watercress, so I have to put that one in there for sure, but lots of other green leaf foods are packed vitamins. Rocket leaves [in the states we call it Arugula] are also excellent sources of vits, A, C and K. Citrus fruits are very well known for their vitamin C content, but other fruits likes cherries are a lot higher in their vit C content.
Some fun ones to consider are dark chocolate and coffee, which are both high in a group of chemicals called flavonoids which incorporates a large group of chemicals that act like antioxidants and although include some vitamins are more than just vitamins. Onions are really high in a chemical called quercetin which has antioxidant properties and is really helpful for blood flow and blood pressure. Ginger and garlic have lots of anti-inflammatory properties also associated with positive heart health. Beetroot and runner bean/green beans are known to be high in nitrates which help keep our arteries flexible (watercress is also high in nitrates).
Spinaca Farms: What is the best way to prepare antioxidant-rich veggies and fruits to maximize their preserve their nutritional value and why?
Dr. Fogarty: You have a funny way of really hitting on the questions of hot topic!
Some might say fresh is best but frozen from fresh isn’t particularly bad as you’re getting that goodness looked in straight away. We grow our own greens at home, so I love that approach where possible. There is some evidence suggesting lightly cooking greens is better than raw as it helps with digestion and extraction of some of the key chemicals. So, a minute or two in boiling water for green leaves with two to three minutes for something like broccoli.
There used to be a school of thought that discouraged the cooking of all these sorts of foods but that is changing now so I wouldn’t worry about it too much. Cook it whatever way you like it because you’ll be more inclined to eat it which is better than not. Just don’t murder the poor veg!