Regular readers of my DietDoc articles will know that I enjoy watching the Survivor series immensely.
Not only is it fascinating to follow the trials and tribulations of a disparate group of people drawn from all walks of life trying to cope with situations far removed from their comfort zones, but each and every series so far has included important diet lessons for viewers.
The Survivor SA series that has recently started, probably illustrates the most fundamental diet truth of all: human beings have evolved to eat a varied, and balanced diet.
Only carbs?Although fruit is rich in carbohydrates and sugars for energy, and bursting with protective nutrients like vitamins, minerals and phytonutrients (beta-carotene, lycopene, vitamin C etc.), no one can survive on fruit alone.
Initially, the members of the Rana Tribe were only able to gather fruits in the jungle on their island, and although I am the first person to encourage people to eat as much fruit (and vegetables) as possible, man can not live on fruit alone.
One thing the abundant fruit supply will ensure for the Rana Tribe is that they will be much less prone to infections and their wounds will heal more rapidly in the weeks to come.
In contrast, the members of the Aguila Tribe were well supplied with delicious fish bursting with proteins – all thanks to the fishing skills of Mzi.
In addition, they were able to cook their fish from the beginning, not only because they had the savvy to make fire, but they also ironically won a flint in one of the first challenges (something the Rana Tribe would sacrifice a lot to have!).
Cooking makes protein foods like fish more palatable and much easier to digest. But the members of the Aguila Tribe were not really satisfied with their high-protein diet (adherents of Atkins-type diets, take note!). Their lack of stamina in some of the immunity challenges showed that they were carbohydrate-deprived.
Carbs are still the best source of energy for physical activity. This is something that body builders and athletes should keep in mind when they insist on eating masses of protein and neglect to eat sufficient carbs to support their strenuous exercise programmes.
No carbs and you can eat all the protein in the world, without success. To build muscles, you need plenty of carbs as fuel for the exercises you do to grow those muscles, and a moderate protein intake – not the other way around!
Because of their lack of nutrients such as beta-carotene and vitamin C, which are found abundantly in fruit, the Aguila Tribe will be plagued with sores that won't heal as their time on the island progresses.
What happened to Jude?
Jude's sudden collapse got me thinking. She said that she was suffering from low blood pressure, but I suspect that she was actually suffering from hypoglycaemia or low blood sugar levels.
The Aquila Tribe had a wonderful supply of fish at their disposal, which if combined with a little salt water (rich in sodium), should have kept Jude's blood pressure at manageable levels. But despite this, she still felt totally weak and had no energy to continue.
If she was actually suffering from low blood sugar instead, then her collapse makes sense. She felt weak, depressed and demotivated, prone to tearfulness and exhaustion – all typical symptoms associated with low blood sugar.
People who suffer from hypoglycaemia will know that all it takes is a small portion of sugar (not such a good option), or a handful of dried fruit (a good option, especially raisins or dates which also have a low GI) to banish those dreaded symptoms of lethargy and weakness.
If Jude had landed up in the Rana Tribe who are eating fruit with its high carb content all day, I bet she would have lasted the course and even been one of the last four or two Survivors standing.
The balanced diet
So, while we watch the Survivors SA battling it out on their romantic islands, it is good to keep in mind that human beings are omnivores. The term 'omnivore' means 'to eat everything'. And that is what we all require.
We have evolved to eat a balanced diet that contains carbs, protein and fat. We need variety and we need all three of these so-called macronutrients to function properly. Did you see how happily the Survivors SA cooked and ate their modest portions of rice? Rice as a carbohydrate is full of energy to fuel activity and rev up blood sugar levels.
Readers who try to cut out any one of the three macronutrients, carbs, proteins or fats, will find themselves in the same kind of trouble as the Survivors. Cut out all carbs and you will feel tired to exhaustion, listless, irritable, confused and weak.
Cut out all protein and your body will not be able to produce important body components such as red blood cells or do vital repair jobs. Cut out all fat and your body won't be able to make essential components like hormones and you will rapidly develop an essential fatty acid deficiency.
Try to keep the example of the Survivors SA in mind – even if you are slimming – and include all three macronutrients in your diet. This is the sensible thing to do. After all, you don't want your torch to be extinguished, do you? – (Dr Ingrid van Heerden, DietDoc, September 2006)
More on Survivor SA
Survivor: food and water