In the United States, the South has the highest incidence of kidney stones, a region where sweet tea consumption is very common.

Conventional wisdom has held that consumption of too much calcium can aggravate the development of kidney stones, since the most common type of stone is seems to be made up largely of calcium. However, strong evidence has accumulated demonstrating that low-calcium diets are actually associated with higher stone risk.

Certain foods may increase the risk of stones: spinach, chocolate, peanuts, cocoa, tomato juice, grapefruit juice, apple juice, soda (acidic and contains phosphorus), all types of tea, and coffee (high levels of oxalate).

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Other drinks are associated with decreased risk of stones, including wine, lemonade and orange juice. Although it has been said that the diuretic effects of alcohol can result in dehydration which is important for kidney stones sufferers to avoid, no research has demonstratedthat it increases the likelihood of kidney stones.

A high protein diet may partly be to blame. Protein from meat and other animal products is broken down into acids. The body takes calcium from the bones to balance the acid in the meat. The kidney filters the blood and stores the calcium particles which have bonded with the acids. When more meat or dairy is eaten, more calcium is found in the kidneys. Over time, and when not properly removed, these particles bind together to form stones.

Quite often if you cut down on the amount of red meat that you eat your risk of kidney stones drops dramatically.

Drinking plenty of water to make sure that the urine is always dilute helps as well.