Transcript Vitamins
Carbohydrates Presented by Janice Hermann, PhD, RD/LD OCES Adult and Older Adult Nutrition Specialist Chemistry of Carbohydrates Carbohydrates Are Made Of: Carbon (4 Bonds) Oxygen (2 Bonds) Hydrogen (1 Bond) Carbohydrates Monosaccharides Disaccharides Simple Carbohydrates (Sugars) Polysaccharides Complex Carbohydrates (Glycogen, Starch, Fiber) Monosaccharides One Sugar Molecule Glucose Fructose Galactose Same Chemical Formula Different Structure Effects Sweetness And Absorption Disaccharides Two Sugar Molecules Maltose = Glucose + Glucose Sucrose = Glucose + Fructose Lactose = Glucose + Galactose Polysaccharides Many Sugar Molecules Glycogen Liver Muscle Starch Fiber Digestion Mouth (salivary amylase) Stomach (HCl and pepsin) Small Intestine (pancreatic amylase) Intestinal Wall (disaccharidases) Maltase (maltose to glucose + glucose) Sucrase (sucrose to glucose + fructose) Lactase (lactose to glucose + galactose) Lactose Intolerance Lactase activity declines with age and for certain racial groups. Lactose remains undigested and is not absorbed. Undigested lactose moves into the large intestine where it absorbs water causing bloating, abdominal discomfort and diarrhea. Undigested lactose becomes food for intestinal bacteria which produce irritating acid and gas, further contributing to discomfort and diarrhea. Absorption Lining Of The Mouth Small Intestine Some Fructose Converted To Glucose Fructose Absorbed Slower Liver Fructose and Galactose Converted To Glucose Metabolism Storage Of Glucose As Glycogen Storage Form Of Glucose In Animals Liver Glycogen Brain, Nerve Cells, Developing Red Blood Cells Muscle Glycogen Glycogen Storage For Hours Not Days Lose Water When Breakdown Glycogen Metabolism Using Glucose For Energy Primary Role Of Glucose 38 ATP/glucose Brain, Nerve Cells and Developing RBCs Metabolism Making Glucose From Protein Protein Converted To Glucose Fat Can’t Be Converted To Glucose If Carbohydrate Inadequate, Converts Protein To Glucose For Brain, Nerve Cells And Developing RBCs Adequate Carbohydrate Spares Protein Metabolism Using Fat for Energy Inadequate Carbohydrate, Fat Used For Energy For Other Cells Fat Broken Into 2-C Fragments And Converted to Acetyl CoA Overloads TCA Cycle 2-C Fragments Combine Forming Ketone Bodies, Can Lead To Ketoacidosis Metabolism Converting Glucose To Fat More Glucose Than Needed For Energy Or Glycogen Converted To Fat And Stored Maintaining Blood Glucose Important To Maintain Blood Glucose Too Low (Weak/Dizzy) Too High (Confused/Difficulty Breathing) Extremes Either Way Can Be Fatal Regulating Hormones Glucose Too High - Insulin Stimulate Body Cells To Take Up Glucose Stimulates Glycogen Synthesis Stimulates Triglyceride Synthesis Glucose Too Low - Glucagon Stimulates Liver To Breakdown Glycogen Falling Out Of Range If Blood Glucose Regulation Fails Diabetes Hypoglycemia Glucose May Be Modified As Part Of Treatment, But Hormonal Regulation Or Obesity (For Type 2 Diabetes) Is The Cause Not Glucose Glycemic Index Usefulness of glycemic index controverseal Controversy on health impact Practical utility limited Few foods have glycemic index determined Those that have based on wide variations Glycemic index may be unnecessary Current guidelines already suggest many low glycemic index choices; whole grains, legumes, vegetables, fruits and milk products. Eating frequent, small meals spreads glucose absorption across the day and thus offers similar metabolic advantages to eating foods with a low glycemic response Glycemic Index Effect Of Food On Blood Glucose Glycemic Index Differs Amount of carbohydrate consumed Nature of starch Type of sugar Preparation methods Fat content Fiber content Most foods are eaten in combination in a meal Fasting and pre-meal blood glucose Types Of Sweeteners Caloric Sweeteners Sugars Sugar Alcohol Non-Caloric Sweeteners Sugars (provide cal Includes Many Caloric Sweeteners Refined Sugars Lactose Corn Sweeteners Glucose Invert Sugars Dextrose Maltose Honey High Fructose Corn Syrup Syrups Concentrated Fruit Juices Health Effects of Sugars Nutritional Deficiencies Sugar Can Only Contribute To Deficiencies By Displacing Nutrients Sugars Are Not “Bad” But Nutrient Dense Foods Must Come First Amount Of Sugar Depends On Calories Available Beyond Those Needed For Nutrients Health Effects of Sugars Tooth Decay Sugars And Starches Contribute To Decay Bacteria In Mouth Ferment Sugars And Produce Acid That Dissolves Enamel Sugar Only One Of Many Factors How Long Food On Teeth How Often Food Eaten Dental Hygiene Health Effects of Sugars Diabetes Hormonal regulation or obesity (in case of type 2 diabetes) causes diabetes - not sugar Carbohydrate intake, including sugar, may be modified as part of the treatment for diabetes but it is not a cause For people with diabetes, attention is first given to total amount of carbohydrate in the diet rather than the source Health Effects of Sugars Hyperactivity/Misbehavior In Children Controlled Studies Failed To Show An Adverse Relationship Between Sugar And Hyperactivity Or Misbehavior In Children Carbohydrates, Including Sugars, Stimulate Production Of Serotonin, Makes A Person Sleepy And Sluggish Health Effects of Sugars Heart Disease Normal Sugar Intakes Do Not Raise Triglycerides, If Calories In Balance Very High Intakes Of Sucrose And Fructose Can Increase Triglycerides Glucose Causes Insulin Release Some People Over Produce Insulin In Response To High Glucose Or Carbohydrate Other dietary factors such as total fat, saturated fat, and obesity have a much stronger association with heart disease than sugar intake. Health Effects of Sugars Obesity Obesity Due To Energy Imbalance No Direct Connection Between Sugar And Obesity, Unless Excess Sugar Containing Foods Leads To Energy Imbalance Foods High In Sugar Often High In Fat Increase In Calorie Intake Has Come From Carbohydrates, And Primarily Soft Drinks Sugar Alcohols Provide Calories, But Fewer Than Sugars Because Not Completely Absorbed Products With Sugar Alcohols Can Be Labeled “Sugar Free” or “Reduced Calorie” Incomplete Absorption Can Cause Gas, Abdominal Discomfort and Diarrhea Real benefit of using sugar alcohols is that they do not contribute to dental caries Non-Caloric Sweeteners FDA Approved Non-Caloric Sweeteners Name Sweetness ADI Saccharin Sweet & Low 450x 5 mg/kg Aspartame NutraSweet 200x 50 mg/kg Equal Acesulfame K Sunette 200x 15 mg/kg Sucralose Splenda 600x 5 mg/kg Neotame 8,000x 18 mg/day Non-Caloric Sweeteners FDA Petitioned Non-Caloric Sweeteners Cyclamate Alitame Accepted Daily Intake (ADI) Amount a Person Can Safely Consume Everyday Over A Lifetime Without Risk Conservative Level with a wide margin of safety Safety Of Non-Caloric Sweeteners All Compounds Toxic At Some Dose Question Is Whether Non-Caloric Sweeteners Are Safe In Quantities People Normally Consume And Potentially Abuse Saccharine Safety Used Over 100 Years In US Not Metabolized By Body, Rapidly Excreted, Does Not Accumulate In Body Originally on GRAS List Safety Questions Arose In 1977 Rat Study Suggested Large Doses Increased Risk Of Bladder Cancer Saccharine Safety Large Human Studies Do Not Support An Association Between Saccharine And Cancer For Population As A Whole Subgroup May Have Increased Risk Aspartame Safety Composed Of: Phenylalanine Aspartic Acid Methyl Group Extensive Studies Document Safety, Except For People With PKU Phenylketonuria (PKU) Inherited Disease Were Can’t Handle Excess Phenylalanine (1:10-15,000) Accumulation Of Excess Phenylalanine and By-Products Can Cause Irreversible Brain Damage Newborns Screened For PKU Phenylketonuria (PKU) Strict Diet Providing Phenylalanine For Growth But Not Damage Aspartame Products Carry A Warning Someone With PKU Can Handle Aspartame In A Diet Soda, But Children With PKU Need Phenylalanine From Nutrient Rich Foods Methyl Group During Metabolism: Methyl Group ⃗ Methanol ⃗ Formaldehyde ⃗ Carbon Dioxide Amount Produced Fall Below Levels That Would Cause Harm Many Juices Produce More Methanol Than Aspartame In A Diet Soda Other Accusations No Credible Evidence Links Aspartame To: Multiple Sclerosis Lupus Seizures Brain Tumors Birth Defects Other Accusations Some People Claim They Have Unusual Sensitivity To Aspartame Double Blind Studies Have Failed To Reproduce Reactions In Conclusion, Except For People With PKU, Aspartame is Safe. Acesulfame K Safety FDA Approved Acesulfame K In 1988 After Reviewing 90 Safety Studies Some Groups Believe Acesulfame K Caused Tumors In Rats FDA Concluded Tumors Were Not Caused By Sweetener Sucralose Safety FDA Approved Sucralose In 1998 After Reviewing 110 Safety Studies Neotame Safety FDA approved neotame in 2002 after reviewing 110 safety studies Neotame also contains phenylalanine, aspartic acid , a methyl group and an additional side group which blocks digestive enzymes from separating phenylalanine and aspartic acid As a result, the amino acids are not absorbed Neotame does not have to carry a warning for people with PKU