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					The skinny on artificial sweeteners and weight gain
Presented by Ann Cohen and Jessica Kovarik

Taste: how
Groups of taste cells on papillae (bumps) Chemical binds with taste cell
 Depolarization of nerve fibers  action potential to brain  Adaptation of nerve transmittion

Taste: what and why
5 tastes: salty, sour, bitter, umami, and sweet
 No longer taste ‘zones’

Taste and survival
 Avoid bitter  Seek out sweet

Sweetness abounds
Sugar = Carbohydrates
 Simple and complex
Main source of energy (4 calories per gram) Occur naturally in foods and added to foods

Simple sugars:
 Sucrose = glucose + fructose
Table sugar

 Lactose = glucose + galactose

 Maltose = glucose + glucose
Germinating grains

Sweetness abounds
Other natural sweeteners:
 Honey, molasses, maple syrup, corn syrup, high fructose corn syrup  Sugar alcohols or polyols, such as mannitol, sorbitol, isomalt

Sweet energy
Nutritive sweeteners
 Contain calories  Honey, HFCS, table sugar, maple syrup, etc.

Nonnutritive sweeteners
 Reduced or no calories  Sugar alcohols and artificial sweeteners

Getting 1+1=1: artificial sweeteners
Low-calorie sweeteners
 Sweet taste with fewer or no calories  Food and Drug Administration approval

Six intense, low-calorie sweeteners:
 Saccharin – Sweet’N Low/Sugar Twin  Acesulfame potassium (Ace-K)  Aspartame  Neotame  Sucralose - Splenda  Tagatose

Getting 1+1=1: artificial sweeteners
Sucralose aka Splenda
 Heat stable = use for baking  3 chlorine atoms instead of hydroxyl groups  600 times sweeter than sugar  Created from sugar, so tastes similar to sugar
Body not able to break it down

Getting 1+1=1: artificial sweeteners
 Natural sweetener extracted from plants  Not FDA approved, so sold as a supplement  Body cannot metabolize, so no calories  Studies inconclusive about safety: some show no adverse reactions, others suggest smaller offspring

Rumor has it sugar causes…
 Contact time of bacteria, not type of food leads to decay  i.e.: bread can be worse than caramel

 No scientific research to support  Is it the sugar or the environment?  May have a calming affect

Rumor has it sugar causes…
 Important to monitor to control diabetes

 Energy imbalance leads to weight gain

High fructose corn syrup
What is it?
 Corn starch converted to glucose  Glucose isomerized by enzymes to 42% or 55% fructose  Named ‘high fructose’ to distinguish from glucose corn syrup  Sweet taste, low cost, easy to use resulting in wide use
Soft drinks, fruit drinks, baked goods, processed foods, dairy products

High fructose corn syrup
Media claims HFCS causes obesity
 Increase in obesity coincides with increased HFCS use
i.e.: added to soft drinks in early 1980s But obesity also problematic in countries where HFCS use is not as prevalent

High fructose corn syrup
Media claims HFCS causes obesity
 Fructose converts to fat easier than glucose
Absorbed at different site by different mechanism Any fructose metabolized same
 HFCS vs. sucrose

Fructose metabolized differently than glucose once in the cell

Fructose verses glucose
 Glucose causes insulin to be released  Fructose does not stimulate insulin release

 Glucose used by the brain and helps sense satiety

Fructose verses glucose
 Increased by insulin release  Increased leptin  decreased food intake
Controls appetite

 Glucose  insulin release increased leptin  decreased food intake

High fructose corn syrup verdict
No evidence to support HFCS contributes significantly to obesity Energy imbalance leads to obesity

Sweeteners and obesity
Artificial sweeteners may cause disruption in body’s ability to gauge caloric density Body appears to gauge calories based on thickness
 Semi-solid and liquid foods/beverages inhibit body’s ability to accurately compensate

Sweeteners and obesity
Obesity has continued to rise as use of artificial sweeteners has risen Multi-factorial problem
 Energy balance: energy in and energy out  Sugar = calories
Excess calories (and inactivity) = weight gain Weight balance = energy out vs. energy in

Laboratory ideas
Tooth Decay
 Explores the effect of various liquids on decaying teeth

Sugar composition of beverages
 Determine the sugar content of various beverages
All the same type: such as juice or soft drinks Compare different types: such as milk, juice, soft drinks, water, etc.

Experiments with soft drinks

Resources for teachers
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         Physiology of taste. Accessed June 12, 2006 from Schorin MD. (2005). High fructose corn syrups, part 1. Nutrition Today, 40(6), 248-252. Hein GL, Lineback DR, Storey ML, & White JS. (2005). Highs and lows of high fructose corn syrup. Nutrition Today, 40(6), 253-256. Science fair projects on tooth decay. Accessed June 12, 2006 from Juices. Accessed May 31, 2006, from Which beverage contains the most sugar? Accessed May 31, 2006, from Duyff RL. (2002). Complete food and nutrition guide. 2nd ed. Hoboken, New Jersey: Wiley. Physiology of taste. Accessed June 13, 2006, from Study: artificial sweeteners may disrupt body’s ability to count calories. (2004). Purdue News. Accessed June 13, 2006, from

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