1. Lecture 4b- 1 October 2014 Fibre metabolism and regulation Most of this lecture derived from Chapter 4 of Gropper

2. Outline of lectures 4a,b Definition of Dietary Fibre Plants and Fibre Dietary Fibre

3. Outline of lectures 4a,b Some Properties-dictate physiological and metabolic effects of fibre a) Water Solubility b) Water Holding/Hydration Capacity as well as viscosity Slowed Gastric emptying Reduced mixing of gastrointestinal contents with digestive enzymes Reduced enzyme function Decreased nutrient diffusion rate Altered small intestine transit time

4. Outline of lectures 4a,b Some Properties-dictate physiological and metabolic effects of fibre c) Absorption or Binding Ability Diminished absorption of lipids Increased faecal bile excretion Lowered serum cholesterol Altered mineral balance

5. Outline of lectures 4a,b Some Properties-dictate physiological and metabolic effects of fibre d) Degradability or fermentability Fermentable fibres Increased water and sodium absorption in colon Mucosal cell proliferation Provision of energy Acidification of luminal environment Non-fermentable fibres Detoxification Increased faecal bulk

6. Outline of lectures 4a,4b Recommended Intake of Fibre Implications in Disease Prevention and Management Fibre-Based Herbal Medicines

7. Outline of lectures 4a,b Summary

8. More Detailed Information Dietary Fibre Recommended Intake of Fibre/Implications in Disease Prevention and Management 25- 35 grams per day-DRI-40 tops, 50 obstruction soluble fibre- hypocholesterolemic -hypoglycemic insoluble fibre- laxative

9. Dietary Fibre How is fibre metabolism regulated in humans? A few examples -intake(form and quantity) -food preparation -regulation of bacterial enzymes and pathways since we cannot use our own enzymes to digest.

10. Fibre-Based Herbal Medicines Echinacea -few controlled studies -immune response boost-prevention or treatment of cold, flu or other infections active agents -hmw polysaccharides among others -side effects-allergic reactions may occur -use in systemic or immune system dysfunction is contraindicated

11. Fibre-Based Herbal Medicines Ginseng -cancer prevention -fatigue reduction -few controlled studies -active agents-saponin glycosides and ginsenosides- modulate hormones and central nervous system function -side effects-negative interactions with warfarin

12. Fibre-Based Herbal Medicines Ginkgo biloba -vascular flow -free radical scavenger -few controlled studies- -active agents-flavone glycosides-see above for effects -side effects-headaches, dizziness, palpitations

13. Fibre-Based Herbal Medicines Garlic -lower cholesterol -anti-platelet aggregatory - a number of controlled studies- -active agents-allicin-see above for functions -side effects-heartburn, flatulence -anticoagulant function synergy

14. Fibre-Based Herbal Medicines St. John's Wort -depression -anxiety a few well- controlled studies- -active agents-MAO inhibitor-fights depression -side effects-fatigue, allergic reactions, photosensitivity

15. Fibre-Based Herbal Medicines Golden seal -canker sores a number of controlled studies- -active agents-alkaloids-see above for functions -side effects-none reported

16. Fibre-Based Herbal Medicines Glucosamine -rheumatoid arthritis

17. Fibre-Based Herbal Medicines Chondroitin sulphate -rheumatoid arthritis

18. Fibre-Based Herbal Medicines Regulatory considerations what should be regulated, how and by who?

19. Fibre-Based Herbal Medicines Summary-figure 5.2 Gropper -no satisfactory definition of fibre -SCFAs provide energy therefore fibre is energy yielding -varied soluble and insoluble fibre content in different foods-implications for such differences?