As mountaineers ascend the world’s highest peaks they know that above 8,000 metres they have entered the death zone. At this level oxygen is so scarce that the human body can no longer acclimatise. Indeed the highest permanent human habitation is a fair bit lower – La Rinconada in the Peruvian Andes at 5,100 meters.
Time in the death zone is at a premium, the climber must achieve their goal and descend. To remain long is to die.
So it is with my weight loss diets. Somewhere between 5,000 and 8,000 grams my body ceases to acclimatise. Progress ceases and the journey downhill begins. The summit beckons, I linger hoping that I will find the strength to continue but alas it was never to be.
In this I am not alone …
A search was conducted for weight-loss-focused randomized clinical trials with >or=1-year follow-up. Eighty studies were identified and are included in the evidence table.
… A mean weight loss of 5 to 8.5 kg (5% to 9%) was observed during the first 6 months from interventions involving a reduced-energy diet and/or weight-loss medications with weight plateaus at approximately 6 months. In studies extending to 48 months, a mean 3 to 6 kg (3% to 6%) of weight loss was maintained with none of the groups experiencing weight regain to baseline. In contrast, advice-only and exercise-alone groups experienced minimal weight loss at any time point. Franz et al.
I started cycling five months ago. The distance covered each week has slowly increased. Last week it passed 200 km for the first time. The one long ride each week has also increased. The longest so far is 80 km. A kilogram a month melted without conscious dietary modification over the first three months. I have now been on a low carb high fat diet for two months and a further six kilograms have departed.
Is my diet in the death zone?
It doesn’t feel like it. My trousers are walking around looking for a decent bum to fill them, my belt is distraught at the loss of the companion that for so long bore its imprint but I feel good. Per ardua ad astra. Carpe diem. Et cetera.
The greatest challenge is ahead.