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Energy, Diet and Aging: The Roles of Photosynthesis and Bioenergetics in Energy

By: Peter T. Pugliese, MD
Posted: September 10, 2009, from the October 2009 issue of Skin Inc. magazine.

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One hundred grams of sucrose is converted to 100 g of glucose. In the mitochondria, a single molecule of glucose will yield 36 molecules of ATP. The task at hand is to convert 100 g of glucose first to molecules of glucose then to molecules of ATP. A molecule weight of a substance in grams is called a mole, or m. Glucose has a molecular weight of 180 g/m, so divide 100/180 and get 0.55 m. Now, how many molecules of glucose is that? A mole of any substance will contain 6.02 x 1,023 molecules, which is very big numberd. Multiply 0.55 x 6.02 x 1,023 = 3.31 x 1,023 molecules in 0.55 m of glucose. Now each molecule of glucose makes 36 molecules of ATP. Multiply the two numbers 36 m x 3.31 x 1,023, resulting in 119.16 x 1,023 molecules of ATP, divided by 6.02 x 1,023 ( to get back to moles), with the answer of 19.8 moles of ATP. The weight of one mole of ATP is 507 grams, so multiplying 19.8 x 507 we get 10,038.6 grams of ATP or 10,039 kilograms of ATP from one soda. (To get pounds of ATP multiply 10,039 x 2.2 = 22,086 pounds.) Convert moles of ATP to kilocalories (kc) multiply by 7.3 kc/m will yield 7.3 kc x 19.8 m of ATP = 144.5 kc, or 604992.6 joules.

The energy in one joule will provide the energy to lift one pound to a height of nine inches. Therefore, if you want to lift an object weighing 10 pounds to counter height (36 inches), it would require about 40 joules, not a lot of energy. On the other hand, a piece of buttered toast contains 315 kilojoules, that is 315,000 joules! With that much energy you can jog six minutes, or walk fast for 10 minutes, or light a 60 watt bulb for 1-1/2 hours. One joule in everyday life is a very small quantity, so instead international nutritional calories are used. A heat calorie is a small quantity—it is the amount of heat required to raise a gram of water one degree centigrade, so a large quantity is needed. The international nutritional calorie is designated by a big C and is equal to 1,000 small heat calories. If a calorie is compared to joules, it would take 4,186.8 joules to equal one nutritional calorie (C).

One international nutritional calorie can supply enough energy to lift an adult human two stories high. Remember that one calorie equals 1,000 (heat) calories, which converts to 4,200 joules (rounded). One joule of energy is enough to lift 1/10 of a kilogram (about 1/4 pound) one meter in the air. One calorie, or 4,200 joules can lift a 70 kg (154 lb) person six meters into the air. Do you realize that if you eat one peanut, which contains 1.8 C, you will need to walk up a four-story building to burn up that peanut?