Scottish students have launched a campaign to overturn a ban on gay and bisexual men donating blood.
Students say gay and bisexual men should be able to give blood
The National Union of Students (NUS) claims current guidelines are outdated and discriminatory - and stop thousands of people saving lives.
Under the current policy, men who have sex with men are banned as they are classed as of a higher risk of passing on sexually transmitted diseases.
The Scottish National Blood Transfusion Service (SNBTS) defended the policy.
Students at Robert Gordon University (RGU) in Aberdeen launched the Scottish campaign on Thursday, after similar protests at universities in England.
Matthew Middler, Lesbian, Gay, Bisexual and Transgender (LGBT) officer at RGU, said they were urging fellow students to write to their MPs about the issue.
Campaigners were also handing out information packs and donor-style cards, reading "Please give blood because we can't".
Mr Middler said: "There is a major blood shortage yet there is a ban on any man who has had sex with another man donating.
"We just find this absolutely ridiculous.
"The view that all gay men have unsafe sex is one that is outdated and homophobic.
"This is about raising awareness - a lot of people are really surprised and shocked when they hear about this policy, especially in recent years with Scotland coming so far in terms of sexual equality, with things like civil partnerships."
Experts say gay people are at higher risk of infection
Scott Cuthbertson, NUS Scotland's LGBT officer, said: "We believe it is not sexual orientation that makes you high risk, it is your sexual practices.
"There are gay and bisexual men who don't engage in high-risk sexual practices and therefore they should be allowed to give blood."
Edinburgh University and Stirling University are also expected to campaign.
However Dr Moira Carter, national donor services manager for the SNBTS, said: "The reason we ask men who have had sex with men not to give blood is because our up-to-date data shows these people are at higher risk of carrying blood-borne viruses.
"We are trying to look after the patients who receive blood."