The passage is mainly about ................ .

People have been buying less and less candy
since the 1960s for a variety of reasons. First,
there is much competition from other kinds of
snacks. A greater Interest in health and
nutrition has also tended to lower demand.
Nutritionists warn against eating too much
refined sugar and suggest eating fruit and
other more nutritious snacks instead. Dentists
warn of the potential harm to teeth by sugar.
And with the slim look increasingly
fashionable, people have naturally tended to
shy away from overindulgence in sweets
because they are very fattening. Nevertheless,
the candy industry is still very large. In 1990,
United States' annual sales totalled more than
8 billion dollars. The company ranked first in
sales in the United States was Hershey Foods,
which first began mass-producing milkchocolate
bars in 1894.