The annual health-care costs for people who are extremely obese are almost twice those of normal-weight people. Very sobering is the fact that severe obesity is increasing at a much faster rate than moderate obesity, quadrupling from 1986â2000.6.
As a sea is connected to the oceans, which are salt water, most seas are also salt water. This is not a distinguishing feature between a sea and a lake, however, as lakes are more commonly freshwater but can be salty depending on their source and their surroundings.
The world's largest lake is the salty Caspian Sea at 143,200 square miles (370,886 km2). The Caspian Sea is surrounded by Russia, Azerbaijan, Iran, Turkmenistan, and Kazakhstan. The world's second largest lake, and the world's largest freshwater lake is North America's Lake Superior at 31,700 mi2 (82,103 km2).