With Gift Aid, your generous donation of £10 would be worth £12.50 at no extra cost to you.
I am a UK taxpayer and I understand that if I pay less Income and /or Capital Gains Tax than the amount of Gift Aid claimed on all my donations in the relevant tax year, it is my responsibility to pay any difference.
To take care of your health, you need to consider a range of health issues, not just HIV. An active and healthy lifestyle will reduce your risk of having other health conditions on top of HIV.