Stay safe & healthy
Belize City is the most dangerous area in Belize, although it's very easy to be safe there. Remain in the tourist zone that runs just north of the marina to the southern extension to the east of the main canal. There are plenty of khaki tourist police monitoring the area and, should you have a problem, feel free to approach them. Just exercise common sense and do not go wandering around alone after dark. Stay near tourist areas or other commercial zones. The south side of Belize City is beautiful as well as dangerous. Otherwise, Belize City is a great place to go if you want to eat, learn, or shop.
Other areas of Belize are generally safe, but like any other place in the world, one should always have some skepticism when dealing with strangers. Most are genuinely helpful, but it never hurts to be cautious.
Under Section 5(1) of the Immigration Act, the government is entitled to deny LGBT travelers entrance to Belize. There are also no legal protections in place for victims of anti-gay discrimination in Belize.
Belize is a relatively healthy country. Bottled water is a must in most areas. And, unless you eat only at ultra-touristic restaurants, dysentery will probably strike at some point; be prepared with over-the-counter medication and prescription antibiotics.
The CDC lists all of Belize except Belize City as a malaria risk area, and recommends the antimalarial drug chloroquine. Dengue fever is also a risk in Belize. Other drugs may also be recommended in certain circumstances - consult a qualified professional specialist.
Insect/mosquito bites should be prevented with appropriate clothing, repellents and insecticides, and bed nets if sleeping in non-air-con/unscreened rooms.
The sun, as anywhere else in the tropics, is very intense. A hat, high-SPF sunscreen, and sunglasses should do you fine.
Many places in Belize are very hot and humid, and dehydration is a risk. An expat suggests to drink as much water as you want, and then drink that much again.
The adult HIV/AIDS prevalence rate is currently at 2.5% or one in every forty adults, this is notably higher than in most of Europe or Anglo-America and also quite a bit higher than in other parts of Central America like Nicaragua or Costa Rica.