Salty french fries may taste good, but they just contribute to dehydration and obesity. William Voon/EyeEm via Getty Images
Lessons learned from a desert sand ratNature provides a clue to the role these factors play with the desert sand rat Psammomys obesus, a half-pound rodent with a high-pitched squeak that lives in the salty marshes and deserts of Northern Africa. It survives, barely, by eating the stems of Salicornia – the glasswort – a plant that looks a bit like asparagus.
However, when the rat is brought into captivity and given the common rodent diet of about 50% carbohydrates, it rapidly develops obesity and diabetes. But if given fresh vegetables low in starchy carbohydrates, the rodent remains lean. Small amounts of fructose, like that found in an individual fruit, are not the problem – rather it is excessive amounts of fructose that are problematic for human health. Most of us get our fructose from table sugar and high-fructose corn syrup. Intake of these two sugars totals approximately 15% of calories in the average American diet.
Since fructose is made from glucose, production of fructose increases when blood glucose levels are high. This process happens when we eat a lot of rice, cereal, potatoes and white bread; those are carbs that rapidly release glucose into the blood rapidly.Fat provides waterFat has two major functions. The first one, which is well known, is to store calories for a later time when food is unavailable.To be clear, fat does not contain water. But when fat breaks down, it generates water in the body.
What’s more, studies show most people who are overweight or obese don’t drink enough water. They are far more likely to be dehydrated than those who are lean. Their salt intake is also very high compared with lean people’s.