FRUIT FOR THOUGHT
“There is no way that taking a pill can replace eating fruits and vegetables … In theory, one could cram all the good things that plants make—essential elements, fibre, vitamins, antioxidants, plant hormones, and so on—into a pill. But it would have to be a very large pill, and no one can honestly say what should go into such a pill. Or in what proportions. Health issues aside, the biggest drawback is that a pill would always taste like a pill. It can’t give you the earthy smell and taste of a fresh ear of corn, the sweetness of a juicy tomato still warm from the afternoon sun, the crunch of an apple, the festive green of a snap pea or broccoli floret, or the smooth nutty taste of an avocado. Stick with real fruits and vegetables—they taste better and contain a bounty of phytochemicals that don’t come in capsules.”— Prof Walter Willett, Eat, Drink and Be Healthy
It’s hard to imagine dinner time when the spotlight wasn’t on “eat your vegetables”. But it’s not that long ago—a bit over 100 years. The discovery of vitamins and minerals in the early years of the twentieth century was the wakeup call and “Dr Vitamin”—Elmer Verner McCollum (1879–1967) – was a key player in ensuring they had a bigger part of the dinner plate. They were protective foods he said, because “they were so constituted to make good the deficiencies of whatever else we liked to eat”.
It’s not just the leafy ones that matter. It’s all of them, because, as Harvard’s Prof Walter Willet says, “so far, no one has found a magic bullet that works against heart disease, cancer and a host of other chronic diseases as well as fruits and vegetables seem to do”.
We are spoiled for choice in the produce aisles. As well as the proverbial leafy greens (spinach, lettuce and cabbage), we can take our pick from veggies that technically are fruits such as avocado, cucumber, marrow (squash), tomato, capsicum (peppers), and green beans; stems or bulbs such as onion and globe artichoke; stalks such as celery and asparagus; flower stalks and buds such as broccoli and cauliflower; and roots and tubers such as carrots, potato and sweet potato. And there’s more, there are the protein-rich edible dried seeds from the legume family: beans, peas and lentils.
As for fruit, next time someone purses their lips and tells you it’s “full of sugar,” you can sweetly smile back and tell them there’s a smart evolutionary explanation for that and for our sweet tooth. First of all, hunting and gathering are hard work, so discovering ripe fruits dangling on a branch in front of us or bright berries on a bush was a no-brainer. Sweetness told our forebears they were safe to pick and eat. Bitterness, on the other hand, helped them steer clear of fruits with potentially tummy upsetting toxins.
You can then explain that the sweetness comes from natural sugars – typically fructose (fruit sugar), glucose and sucrose ranging from a mere trace in pucker-up limes to almost 60 per cent in dates. And although sugars in themselves aren’t a health food, in fruits they are also accompanied by really good stuff such as fibre, vitamins, minerals and phytonutrients including eye-catching carotenes in orange-fleshed fruits like mangoes, papaya and peaches and anthocyanins in all the blue/purple berries.
Why are fruits sweet? That’s easy. They want us to eat them. Why? Well, look at it from the tree’s point of view. When you are rooted to the spot, you need something mobile to help you disperse your seeds. The sweet, ripe, juicy flesh of a fruit tree’s fruit is an inducement. It tempts us and animals, birds and insects to tuck into it and, one way or another, spread the seeds far and wide. This successful strategy has seen seeds become the original globe trotters.
However, it’s unlikely we humans would make the finals if seed dispersal was an Olympic sport. As competitors, we are outclassed. A thirsty hyena can chomp through 18 tsamma melons in a night then disperse seeds over a home range of some 400 square kilometres (150 square miles). This is impressive, but possibly pales alongside a black bear sitting around gorging up to 30,000 berries in a day, then distributing thousands of seeds over its territory.