I've been an insulin dependant diabetic since I was 8 (almost 16 years) and have been alpine and winter climbing climbing for over 4 years. I have thus far had quite a bit of success - highlights include: Piz Badile North East Face, Cordier Pillar, Dru North Face, Walker Spur, Gervasutti Pillar, Droites North East Spur Direct and Frendo Spur. I thought I'd write a short piece on how I deal with my diabetes in the mountains. I hope this will be of use to other diabetic Alpinists and I would be keen to hear anyone’s thoughts on it as I have had little contact with other diabetic Alpinists.

I am on basal-bolus insulin regime and inject 34units of basal (long-acting) insulin and 7, 7 and 14 units of bolus (short-acting) insulin on a normal non-active day. Before a big route I normally reduce my basal insulin by about 30% from 34 to 24 units. Although I often inject less if I know it's going to be really strenuous and on the second day of climbing depending on the situation.

Whilst moving fast on technical terrain it's hard to have proper full meals. I eat little and often and inject 1 or 2 units of bolus insulin every now and then to compensate. I will inject between 5 and 10 units before meals on bivies depending on how much I eat. These figures are only roughly what I will inject on average.

I find it important to be able to test my blood sugar and inject easily, so I keep my bm meter and bolus insulin pen in my inside chest pocket. This also helps keep my bm meter warm, as far as I know there are no bm meters that work in the cold. If it's not working when you want to test i've found the best way to warm it up is putting it down your pants in between your legs. On multi-day routes I normally carry a spare pen and meter in my sack in case the one in my pocket gets dropped. And take plenty of needles and test strips.

I try and stop to check my blood sugar and inject if necessary as often as I can, but it's often difficult. I find it's all kind of trial and error when deciding how much to inject, and the amount you need to inject in certain situations is going to vary lot from person to person. I always try and err on the high side as hypos are a lot more serious than hypers in the mountains. This had lead me to have quite high blood sugar sometimes when I’ve been climbing, which isn't good especially when you've got limited water. But when you want to be moving fast stopping to deal with a hypo isn't good either, so it's a difficult balance.

As far as food is concerned I carry the same as my non-diabetic climbing partner, plus about 6 packs of dextrose tablets per expected day climbing to treat any hypos. My partner also carries a glucogon pen.

I find that the more I climb in the mountains the more I lean about how my insulin sensitivity changes with different amounts of exercise and exposure to cold. But it's all still a lot of guess work and trial and error. I think it's important to appreciate just how much multiple days of hard exercise and also being cold can increase your insulin sensitivity.

Once when climbing on Ben Nevis for the second day in a row in very cold windy conditions I had injected only 10 units of basal insulin the night before and neglected both testing my blood sugar and injecting any bolus insulin all day (not a good idea, I was being lazy/undisciplined because the weather was so wild, but I felt fine). I had eaten several chocolate bars during the day and when I tested my blood sugar on returning to the tent I expected it to be sky high. I was surprised when it was only 10 mmol/l. I think this demonstrates how drastically the amount of insulin you need can change in certain situations.

When I first read tales of desperate epics in the mountains when I was a teenager I thought that hard serious alpine climbing just wouldn't be possible for a diabetic. But I am now starting to think that anything is possible given the right levels of discipline and control. I haven't been particularly held back my diabetes yet in my climbing and just see it as another obstacle to overcome out of the many obstacles out there.