World Diabetes Day is Saturday. Above, a patient takes a blood glucose test during an event aimed to help people with diabetes cope with their illness at Saint Luka diagnostics medical center in Sofia, Bulgaria, Nov. 13, 2012. Stoyan Nenov/Reuters

Around the world, nearly 350 million people suffer from diabetes, a chronic and debilitating condition where a person's body essentially cannot metabolize the sugar from foods he or she eats. Every year, about 1.5 million people die from complications of the disease. With Saturday marking World Diabetes Day, here's everything you need to know about diabetes, especially as diets and foods that seem ever more rife with sugar.

Diabetes comes in two main forms:

Type 1, typically diagnosed in children or young adults, comprises about 5 percent of those with the disease. Those with Type 1 diabetes cannot produce their own insulin, a hormone that regulates blood sugar and prevents it from reaching harmfully high levels in the bloodstream.

Type 2 diabetes is far more common. The body either produces insulin but is resistant to its effects or simply doesn't produce enough. Type 2 is also called adult-onset diabetes.

If diabetes goes unmanaged or uncontrolled -- there are therapies and dietary and lifestyle changes that can help control blood sugar levels -- it can damage blood vessels, the kidneys, eyes, skin and hearing. In some cases, poor blood flow to the feet makes it necessary to amputate toes, a foot or even part of the leg. The risk of having a heart attack, stroke or other cardiovascular problems also rises with diabetes, as do the chances of going blind.

Why some people develop Type 2 diabetes and others do not isn't fully clear. Being overweight can be a factor, but people who aren't overweight can also develop diabetes. African-Americans, Mexican-Americans, American Indians, native Hawaiians and sometimes Asian-Americans are at greater risk of developing diabetes, according to the American Diabetes Association. Type 2 diabetes also seems to run in families.

An increasing majority of those with diabetes live in low- and middle-income countries, according to the World Health Organization (WHO). About 80 percent of the 1.5 million people whose deaths were linked to diabetes in 2012 lived in such countries, meaning that more people without access to necessary healthcare and medicine are afflicted with the disease and are at ever greater risk of going blind, suffering from organ failure and, eventually, dying from the disease.

The WHO has projected that by 2030, diabetes will be the seventh leading cause of death in the world. The organization blames 7 percent of Type 2 diabetes cases on a lack of physical activity and 65 to 80 percent on being overweight or obese.

In June, a study published in the Lancet found that diabetes rates around the world had risen 45 percent from 1990 to 2013, primarily in Type 2 diabetes. Public health researchers have blamed urbanization, lifestyles that are increasingly sedentary and poor diets -- high in calories derived from refined carbohydrates and sugar -- for the burgeoning global diabetes epidemic.