By Kelvin Hayes

Acidity of liquids is measured using the pH scale. A pH below 7 is consider acidic, while a pH above 7 is considered alkaline. A substance having a pH of 1 is an extremely strong acid, while a substance with a pH of 10 is incredibly basic; a pH of 7 is considered neutral. Fresh water is the closest substance to neutral, hovering just above or below 7. Our different body fluids range from 4.5 to 7.5 pH, with the blood slightly alkaline at 7.35 to 7.45 pH. The average acidity of sodas is approximately 3 pH -- highly acidic, but different sodas vary in their level of acidity.

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The Trouble with Acid

Food or drink that has a high level of acidity shouldn't be consumed in excess, soda especially . Drinking diet or regular soda alters the chemistry of your blood by spiking acid levels. In response, the body pulls minerals like calcium from your bones to absorb the acids. The danger arises when you drink soda frequently, as this results in consistent depletion of the minerals in your body. It also creates an overall lower pH in the body -- a condition that has been linked to increased risk of cancer and other diseases that require high acid levels to thrive.

High Fructose Corn Syrup

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High fructose corn syrup is a synthetic chemical made from corn. It's a substitute for natural sugar that can be preserved more easily and is cheaper to manufacture. High fructose corn syrup is found in nearly every soda on the market today. The average acidity of soda containing high-fructose corn syrup, like Coke or Pepsi, is 2.5 pH. This is pretty acidic considering tap water has a pH level of 7.5 -- near neutral on the pH scale.

Diet Soda

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Diet sodas are slightly less acidic.

Diet sodas are slightly less acidic than full-bodied sodas, with a pH of about 3.5.The average blood pH level must remain within an alkaline range of 7.35 to 7.45 pH.

Least Acidic Sodas

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Sprite is less acidic.

Mug Root Beer, Diet 7-Up, Diet Mountain Dew, Sprite, and Diet Coke are the least acidic of the sodas, with 4.038, 3.706, 3.365, 3.298, and 3.289 pH's respectively.

Sodas that are moderately acidic include: Mountain Dew, 7-Up, Diet Dr Pepper, and Slice Orange, with pH levels of from 3.229, 3.202, 3.169, and 3.059 respectively.

Most Acidic Sodas

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RC cola had the lowest acidity levels.

Bringing in the rear, sodas that are most acidic are: Diet Pepsi,Dr Pepper, Squirt, Lemon Brisk, Pepsi, Coke and Cherry Coke have high acidic levels of 3.031, 2.899, 2.898, 2.525 and 2.522 pH levels respectively.

And the king of soda acidity, with the lowest pH, is RC Cola, possessing a frightening pH level of 2.387.