Fructose

(fruit sugar)

• In sucrose: table sugar
• it is in fruit, honey, and in high-fructose corn syrup
• converted into glucose in the liver

• simple sugar units

• Glucose
• Fructose
• Galactose

Glucose

(dextrose)

• Major monosaccharide in the body
• in bloodstream: blood sugar
• breakdown of starches and sucrose
• source of fuel for cells
• C₆H₁₂O₆

• from lactose (milk and dairy products)
• converted into glucose in the liver

• sugar
• breaks down into glucose + fructose

• milk products
• breaks down into glucose + galactose

• "simple sugars"
• sucrose
• lactose
• maltose

• fermentation
• alcohol production
• breaks down into glucose + glucose

• Polysaccharides
• starch
• dietary fiber

• polysaccharide
• carb storage in plants
• amylose
• amylopectin
• long chains of monosaccharides  (3,000 molecules or more of glucose in a polysaccharide)

• starch
• carb storage in animals and humans
• structure similar to amylopectin
• more sites for enzyme action
• found in the liver and muscles

• straight chain polymer

• highly branched polymer

• undigested starch (body cannot break the bonds)
• insoluble or non-fermentable fiber
  (apple peal)
•            cellulose, hemicellulose, lignin
•            not fermented by bacteria in the colon
•            benefits: cleans the colon, laxative effect, adds bulk to diet (whole grain)
• Soluble or viscous fiber (inside of apple)
•            gum, pectin, mucilage
•            fruit, vegetable, rice bran, psyllium seed
•            benefit: makes you fill full sooner, help lower cholesterol, slow emptying of the stomach helps diabetics with insulin sensitivity

• fiber added to food (provides health benefits)
• Prebiotics- type of functional fiber
•            stimulate growth or activity of beneficial bacteria in large intestine
•            whole grain
• Probiotics-"good bacteria" that help with digestion and protection against harmful bacteria
•            yogurt
•            treat IBS

Carbohydrates in Food

(MyPlate.gov)

• Grains: 15 g/serving
• Vegetables: 5 g/serving
• Fruits: 18 g/serving
• Dairy (milk and yogurt): 12 g/serving
• Protein (beans and nuts: 4-10 g/serving

• made from corn
• 55% fructose
• 45% glucose
• cornstarch mixed with acid or enzymes
•          starch is broken down to glucose
•          some glucose is converted to fructose
• improves shelf-stability and food properties

• brown sugar
• turbinado sugar (raw sugar)
• maple syrup and honey

• Sorbitol
• Xylitol
• Mannitol
• all 2.6 kcals/gram
• excess consumption: laxative effect
• do NOT promote tooth decay

Saccharin (Sweet 'n Low)

(sugar substitute)

• first produced in 1879
• 180-200X sweeter than sugar
• No potential risks in humans
• contrary to misrepresentation
• based on lab studies in rats in the 1960s

Sucralose (Splenda)

(sugar substitute)

• 600x sweeter than sucrose
• heat stable
• excreted in the feces
• tiny amt. digested
• substitutes chlorines for hydroxyl groups on sucrose

Aspartame (Equal, NutraSweet)

(sugar substitute)

• 180-200X sweeter than sucrose
• not heat stable
• composed of phenylalanine, aspartic acid, and menthanol
• complaints of sensitivity
•          headaches, dizziness, seizures, nausea, etc.
• acceptable daily intake 50 mg/kg of body weight (FDA)
•          14 cans of diet soda for one adult per day
• Warning label for Phenylketonuria (PKU)

Neotame

(sugar substitute)

• 7,000-13,000X sweeter than sucrose
• FDA approved
• similar structure to Aspartame
• is not broken down by the body
• heat stable
• safe for use

Acesulfame-K (Sunetteâ)

(sugar substitute)

• Approved by FDA
• 200x sweeter than sucrose

• Not digested by the body
• Heat stable
• Can be used in baking

Tagatose (Naturloseâ)

(sugar substitute)

• Altered form of fructose
• 1.5 kcals/gram
• Does not increase glucose level
• Does not cause tooth decay
• Is fermented by large intestine

Stevia (Sweet Leaf®)

(sugar substitute)

• 100-300X sweeter than sucrose
• Provides no energy
• Generally recognized as safe (GRAS)
• Can not be used as additive in food products

• Salivary amylase
  •Breaks starch to shorter pieces of carbohydrate
  •Saccharides: 1, 2 of 3 molecules of glucose joined
      •Prolonged chewing
• Short duration in the mouth

• Acidic environment
• no further starch digestion

• •Pancreas releases enzymes
  •Pancreatic amylase
  •Absorptive cells in intestinal walls release
  •Maltase
  •Sucrase    
  •Lactase      
  •Monosaccharides are absorbed

• •Reduction in lactase
  •Lactose undigested & not absorbed
  •Lactose metabolized by large intestinal bacteria
  •Causes gas, bloating, cramping, discomfort
  •Primary lactose maldigestion
  •Secondary lactose maldigestion
  •Severe cases called lactose intolerance

• Portal vein to the liver
• Liver can:
•       Transform monosaccharide into  glucose
•       Release glucose back into the bloodstream
•       Store as glycogen (or fat)

• Only a minor amount escapes digestion
• Travels to the colon
• Fermentation by the bacteria
• Acids and gases produced are absorbed
• May promote health of the colon

• Supplies energy
• Protein sparing
• Prevents ketosis
• Regulation of blood glucose
•            Hyperglycemia
•            Hypoglycemia
  

• Role of the liver
  Regulates glucose that enters bloodstream
• Role of the pancreas
  Release of hormone insulin
  Release of hormone glucagon

• Promotes glycogen synthesis
• Increases glucose uptake by the cells
• Reduces gluconeogenesis
• Net effect:  lowers blood glucose

• Breakdown glycogen
• Enhances gluconeogenesis
• Net effect: raises blood glucose

• “Fight or flight” response
• Breakdown glycogen
• Raises blood glucose

• Glycemic Index: Ratio of blood glucose response to a given food

• Large release of insulin
  Increase blood triglycerides level
  Increase fat deposits
  Increase clotting
  Increase fat synthesis in liver
        Rapid return of hunger
• Insulin resistance develops (Type 2 diabetes)

• Controversial
• Focus on fruits, vegetables, beans, and whole grains
• Higher-fiber foods are more nutrient dense

• Filling
• Low in kcal
• Satisfied after eating

Enhancing Glucose Control

• Soluble fiber slows glucose absorption
• Better blood glucose regulation

• Absorption of cholesterol inhibited
• Bile acid absorption reduced
• Risk for cardiovascular disease and gallstones reduced
• Insulin release decreased
  Decrease cholesterol synthesis in the liver
• Blood cholesterol lowered

• RDA is 130 grams/day for adults
• Average U.S. intake is 180-330 grams
• Recommendations vary
  FNB: 45%-65% of total calories
        Nutrition Facts panel: 60%
• Focus on fruits, vegetables, whole grains

• Goal of 14 grams/1000 kcal
  AI is 25 grams/day for women
        AI is 38 grams/day for men
• DV is 25 grams for 2000 kcal diet
• Average U.S. intake:
  14 grams/day for women
  17 grams/day for men

• Type 1 Diabetes
• Type 2 Diabetes
• Gestational Diabetes

• Occurs often in children
  Genetic link
  Auto-immune issue, attack on pancreas
        Distinct symptoms
• Greater risk of kidney disease, blindness, cardiovascular disease, & amputation
• Body stops producing insulin
• Treatment
  Insulin Therapy
  Diet Therapy

• Generally in people > 40 years of age
        Increasing rates in younger individuals
• Prevalence linked to Obesity
• Symptoms mild, vague
• Treatment
  Weight loss
  Oral medications
  Diet therapy
  Insulin

• 25% of adults have it
• High blood triglycerides
• Poor blood glucose regulation
• Hypertension
• Risk factors
  Obesity
  Lack of physical activities
  High simple/refined sugar intake
  Low fiber intake

• Do not readily dissolve in water
• Types of lipids:
  Triglycerides
  Phospholipids
        Sterols (Cholesterol)
• Fats (solid) and oils (liquid)
  9 kcal /gm

• 95% dietary fat absorbed
• Short- & medium-chain (<12 C) fatty acids
  Are water soluble
       Enter the portal system
• Long-chain fatty acids re-form into triglycerides
  Not water soluble
  Enter the lymphatic system

• Water (blood) and oil (fat) are incompatible
• Unique system of fat transportation is needed

• Re-formed into triglycerides
• Packaged into chylomicrons
• Lipoprotein lipase
        Breaks down triglycerides in the chylomicrons
• Chylomicron remnant
  Delivered to the liver

• Made primarily by the liver
• Very-Low-Density Lipoprotein (VLDL)
• Low-Density Lipoprotein (LDL)
• High-Density Lipoprotein (HDL)

• Synthesized by liver and intestine
• High proportion of protein
• Picks up cholesterol from dying cells and other sources
• Transfers cholesterol to other lipoproteins
• Transfers cholesterol directly back to the liver

• Removes cholesterol from the bloodstream
• HDL may block oxidation of LDL
• Reduces risk of cardiovascular disease
• Pre-menopausal women have higher HDL

• An Essential Fatty Acid
         What does essential mean?
• Primarily from fish oil
• Also canola oil, walnuts, flax seeds, mussels, crab, shrimp, and soybean oil
• Need more Omega 3 in diet
  Recommended intake of ~2 servings of fish per week
  Primarily fatty fishes (salmon)

• Found in vegetable oils
• Obtained easily in US diet
  Essential but too much not good
        High intake related to inflammation
• Only need
  ~ 2-4 tablespoons a day

• Archidonic acid (Omega-6 )
  Increases blood clotting
        Increases inflammatory responses
• DHA, EPA (Omega-3)
  Decrease blood clotting
  Reduce heart attack
  Decrease inflammation
  Excess may cause hemorrhagic stroke
  Other possible uses: Lower triglycerides, rheumatoid arthritis, behavioral disorders

• Flaky, itchy skin
• Diarrhea
• Infections
• Retarded growth and wound healing

• Provide energy
• Efficient storage of energy
• Insulation
• Protection
• Transport fat-soluble vitamins
• Some satiety
• Flavor and mouth feel

• No RDA (Rec Dietary Allow)
• AHA recommendations
  20-30% of total kcal from fat
  7-10% can come from saturated/trans fat
       200-300 mg cholesterol/day
• Average U.S. intake:
  33% of total kcal from fat
  13% of kcal from saturated fat
  180-320 mg cholesterol/day

• Up to 35% of total kcal from fat
• Keep saturated fat, cholesterol, and trans fat to a minimum

• Fat intake can be higher as long as saturated and trans fatty acid are minimal
• Eat plenty of fruits and vegetables
• Cut down on red meats
• Cut down on simple sugars and refined carbohydrate
• Promote healthy weight
• Be active

• Myocardial infarction
• Cerebrovascular disease

• Total blood cholesterol > 200 mg/dl
• Smoking
  Increases clotting
        Increases expression of genetic link
• Hypertension (> 139/89)
• Diabetes
  Insulin increases cholesterol synthesis
  Increases the risk for cardiovascular disease

• Low HDL (< 40 mg/dl)
• Age
• Family history
• Blood triglycerides > 200 mg/dl
• Obesity
  Fat around the waist
        Insulin resistance
• Inactivity

• Intense, prolong chest pain
• Shortness of breath
• Sweating
• Nausea and vomiting
• Dizziness
• Weakness
• Jaw, neck, shoulder pain
• Irregular heartbeat

• For those who experience a heart attack
         Or have CVD or diabetes
• www.nhlbi.nih.gov/
• Medication to lower LDL
  Reduce cholesterol synthesis (Statins, “Lipitor”)
        Binds to bile acids for elimination
• Medication to lower blood triglycerides
  Reduce triglyceride synthesis

• See your doctor to assess for other conditions
• Reduce dietary saturated fat and cholesterol
• Increase MUFA and PUFA
• Increase dietary fiber (soluble)

• Found in our body and foods
       As triglycerides
• Saturated fatty acids
•           Solid form at room temperature
• Unsaturated fatty acids
  Liquid form at room temperature
       Cis and Trans forms possible
• Food lipids may contain both saturated and unsaturated fatty acids

• Most common form of fats and oils
• Fatty acids attached to a glycerol
• Glycerol +3 FA’s >>>Triglyceride + 3 H20

• Is the most diet-responsive blood lipid
• Avoid overeating
• Limit alcohol
• Limit simple sugars
• Small frequent meals
• Include fish in the diet: Omega-3 fatty acids can lower triglycerides

• Benecol and Take Control margarines
  Plant stanol/sterol esters
  Cholesterol-lowering effects
  Decrease absorption of cholesterol and lower amount returning via enterohepatic circulation
  Liver takes up more cholesterol from the blood

• Built on a glycerol backbone
• Contains phosphorus compound(s)
• Found in body
• Synthesized by the body as needed
• Component of cell membranes

• Emulsifier: holds onto the fat and the water
  Bile acids
  Lecithins
        Improves food products
• Found in wheat germ, peanuts, yolks, soy beans, organ meat

• Multi-ringed structure
• Do not have a glycerol backbone
• Waxy substance
• Do not readily dissolve in water
• Found in animal foods

• Essential component of cell membrane
• Produced by the liver
• Consumed in diet
         Found only in animal products
• Forms important substances
  Hormones Estrogen & testosterone
        Vitamin D
• Precursor to bile acids
  Used to digest fats & lipids

• Physical activity
   
• At least 45 min/day, 4 days a week
• Don’t smoke
• Eat regularly
• Eat less total fat
• Moderate intake of alcohol increases HDL

• Fat Substitutes

•        Water
              Diet margarine
•         Fiber cellulose
              Maltrin, Stellar, Oatrim
•        Olestra or Olean (links fatty acid to    sucrose)
              Not digested
              FDA approved for fried snack foods
              Fat-soluble vitamins issue

• Process used to solidify an oil
• Addition of H to C=C double bonds
• Increases shelf life
• Formation of trans fatty acid
  (similar to shape of saturated fatty acid)

• Increases risk for cardiovascular disease
• Required on food labels

               Minimize Intake of Trans Fat

• Limit use of hydrogenated fats
• Limit deep-fried foods
• Limit high-fat baked goods
• Limit use of non-dairy creamers

• Limited fat digestion occurs

     Gastric lipase
    Activated by an acidic environment
    Acts on triglycerides containing short- and medium-chain fatty acids

• Primary site of fat digestion
• Hormone cholecystokinin (CCK)
        Stimulates release of pancreatic lipase
• Bile acid released
        Emulsifies digested fat
• Fat is broken down
  To monoglycerides and fatty acids

• Enzymes released
  From pancreas
        From cells of the small intestine
• Broken down to
  Glycerol
  Fatty acids
  Remaining parts