13 - NP for Weight Loss Flashcards
Are any weight loss supplements effective?
NO WAY JOSE
Why do people turn to natural supplements for weight loss even if there is limited evidence?
easy, promised a quick fix
What is the most commonly used criteria to determine weight status?
BMI (kg/m2)
List the weights and BMI relationships
Underweight < 18.5
Normal 18.5 - 24.9
Overweight 25 - 29.9
Obesity > 30
What age is BMI indicated for?
20-65
Who is BMI not indicated for?
Does not apply to infants, children, adolescents, pregnancy, or breastfeeding
Simple concept for weight reduction
energy intake < energy expenditure
What is considered safe weight loss?
<2 lbs/week
Does HC actually promote any OTC products for weight loss?
NO - drugs or natural product therapy cannot replace lifestyle changes for effective, maintained weight loss
List 3 reasons why overweight patients seek dietary supplements for weight loss
- Social stigma of obesity
- Health benefits of weight loss
- Less demanding than accepted lifestyle changes, such as exercise and diet
List the potential affects of supplements
- Increase energy expenditure
- Modulate carb metabolism
- Increase satiety (fullness)
- Increase fat oxidation or reduce fat synthesis
- Block dietary fat absorption
- Increase water elimination
Describe Fat Burners
Claim: “Melt away fat” and increase muscle
Evidence: insufficient
Risks: some products are not authorized for use
List examples of Fat Burners
conjugated linoleic acid, vitamin B5
Describe Carb Burners
Claim: burns carbs
Evidence: lacking
Risks: potentially serious
List examples of Carb Burners
chromium, ginseng
Describe Fat Blockers
Claim: absorption of fat decreased
Evidence: weak, will not work unless on a low calorie diet
Risk: some agents induce diarrhea and block vitamin absorption. Allergic reaction risk for chitosan, because contains shellfish
List examples of Fat Blockers
Chitosan, Hydroxycut (Hydrocitric Acid)
Describe appetite suppressants
Claim: feel full, so eat less
Evidence: few studies done
Risk: unknown due to lack of studies
List examples of appetite suppressants
guar gum
psyllium
hoodia gordonii
glucomannan
Describe NHP Diuretics
Claim: increased water elimination
Evidence: weak
Risks: dehydration, diarrhea, allergy
List an example of a NHP diuretic
dandelion
Describe metabolism boosters
Claim: burn more calories and fat
Evidence: may hep use more energy
Risk: SIGNIFICANT as will increase heart rate and blood pressure
List examples of metabolism boosters
ephedra bitter orange DMAA caffeine green coffee 7-Keto-DHEA catechin capsaicin raspberry ketones
Agents that increase energy expenditure are thought to ?
burn energy as you sit there
“thermogenic agents”
Mechanisms of ephedra
1) A and B adrenergic agonist
A adrenergic agonists cause:
- Peripheral vascular resistance to increase and BP is elevated
- Receptors on smooth muscle cells in the bladder to increase the resistance to outflow of urine
B adrenergic agonists cause:
- Stimulate rate and force of cardiac contraction
- Promotes bronchodilator in the lung
2) CNS Stimulant
3) Enhances release of NE from sympathetic neurons
4) Act as an anorectic by acting on the satiety centre - makes you think you are full
SE of Ephedra
Hypertension Cardiac arrhythmias Insomnia Tachyphylaxis Anxiety and changes in mood Nausea Vomiting
Is ephedra effective?
- Lots of studies with no conclusions
- Ephedrine is not licensed to be sold for weight loss, only as a decongestant
Ephedra has bene linked to many serious side effects such as ?
- heart attack
- arrhythmia
- stroke
- psychosis
- seizures
- death
Describe caffeine
- stimulant
- alkaloid
- occurs naturally in the leaves, seeds and fruit of tea, coffee, cocoa, kola trees and more than 60 other plants
- botanicals such as guarani, yerba mate, kola nut and green tea extract
List some mechanisms of caffeine
- Thermogenic agent (thought to burn energy while you sit)
- Inhibits phosphodiesterase-induced degradation of intracellular cyclic AMP (cAMP)
- Stimulates lipolysis by stimulating lipase
- Stimulates uncoupled respiration
- Antagonizing the negative modulatory effect of adenosine on increased noradrenalin release
- Reduced food intake after caffeine intake
There is a HC warning against what combo of weight loss products ?
ephedra and caffeine
Describe DMAA (dimethylamylamine)
- HC has not authorized use
- Found in weight loss and pre-workout supplements (body building and increasing athletic performance)
- One small study suggested increased calorie expenditure and potentially lipolysis
- No evidence long term
Is DMAA safe?
No - lots of adverse effects:
- High BP
- SOB
- chest pain
- stroke
- psychiatric disorders
Mechanism of catechin in green tea?
- Thermogenic agent
- Believed to have a role in increasing energy metabolism, which may lead to weight loss
- Said to increase a person’s energy output
SE of green tea (from the caffeine)
- insomnia, anxiety, irritability, upset stomach, nausea, diarrhea or frequent urination
- green tea contains small amounts of vitamin K, which can make anticoagulant drugs, such as warfarin, less effective
What is the active ingredient in green coffee?
chlorogenic acid from raw coffee beans before they are roasted
MOA of green coffee
Thought to help control glucose metabolism
- may decrease glucose concentration after a meal
- may decrease glucose absorption in intestines
Also chlorogenic acid thought to inhibit fat accumulation and may alter adipokine levels and body fat distribution
Adverse effects of green coffee
- Appears well tolerated with no significant side effects reported
- Some products decaffeinated, others may contain as much caffeine as regular coffee
- Studies are preliminary and of poor quality, therefore too early to recommend
_______ is a major pungent principle in red hot peppers
Capsaicin
Mechanism of capsaicin ?
- Dose dependently enhancing catecholamine secretion from the adrenal medulla
- Likely based upon B-adrenergic stimulation
SE of capsaicin ?
- skin inflammation
- contact dermatitis
- skin blister
Raspberry ketone is structurally similar to ?
capsaicin and synephrine (from citrus plants)
What are the potential actions of raspberry ketones?
inhibits fat accumulation and inhibition of fat absorption
Raspberry ketones may have a negative effect on what other disease ?
Osteoporosis:
May have a negative effect on bone by stimulating the RANKL pathway
raspberry ketones can also decrease the effectiveness of _____
warfarin
Forskolin is part of the _____ family
mint
Proposed MOA of Forskolin
-Theorized to activate cAMP thereby triggering lipase resulting in a release of fatty acids from adipose tissue
List some Drug interactions with Forskolin
Major:
CCB
Nitrates
Moderate (caution combo):
Anticoagulants
Antihypertensives
CYP P450 2C9 substrates
Adverse effects with forskolin?
- Significant adverse effect not found in tow small clinical trials
- Tachycardia and arrhythmias have been reported
- Avoid in patients with polycystic kidney disease
- IV formulation: flushing and hypotension
List 2 things that modulate carb metabolism
- Chromium
- Ginseng
Which forms of Chromium are active and toxic?
Trivalent - biologically active and found in food
Hexavalent - a toxic form that results from industrial pollution
What is the mechanism of Chromium ?
- Enhances the action of insulin, the so called “glucose tolerance factor”
- Involvement in carb, fat, and protein metabolism
Is Chromium effective for weight loss?
No LOL - none of these products are
SE of Chromium ?
> 1000 mag daily can cause rhabdomyolysis and renal failure
Mechanism of ginseng?
- Ginsenosides
- Carbs are one of the main fuel sources for activity
- Stored in the liver and skeletal muscle as glycogen
- Ginseng appears to mimic insulin
- Improve glucose tolerance
- Lowers blood glucose levels
- Lack of evidence
SE of ginseng
- Usually well tolerated
- Suggested that use be limited to 3 months
- Most common SE are headaches, GI, and sleep
- Caution in ppl with DM
Which NHPs increase satiety?
- Psyllium
- Hoodia
- Guar Gum
- Glucomannan
What is Pysllium
Soluble fibre
Mechanism behind Psyllium and weight loss?
- Combines with water in the stomach to form a gel
- Provides a sense of fullness
SE of Psyllium
Bloating Allergy Nausea Dyspepsia Flatulence Abdominal Pain Diarrhea Constipation
Which agents increase fat oxidation or reduce fat synthesis
- Hydroxycitric acid or garcinia
- Conjugated linoleic acid
Mechanism of hydroxycitric acid ?
- Increase hepatic glycogen synthesis, inhibiting lipogenesis, increased lipid oxidation
- Decrease food intake
- Decrease weight gain
SE of hydroxycitric acid?
- well tolerated
- headache
- gastrointestinal complaints
How do conjugated linoleic acid work?
promoted to induce apoptosis of fat cells
SE of conjugated linoleic acid ?
- Nausea
- Dyspepsia
- Loose stools
What do isolated isomers increase?
hyperproinsulinemia and insulin resistance in patients with abdominal obesity
MOA of Chitosan
block dietary fat absorption
“fat blocker”
What does Chitosan affect since it’s a fat blocker?
Absorption of fat-soluble vitamins (ADEK)
SE of Chitosan
- Safe, except for individuals allergic to shellfish
- Constipation
- Flatulence
What is Dandelion
NHP diuretic - increase water elimination
MOA of Dandelion
- Contains sesquiterpenes, such as eudesmanolides and germacranolides, as well as phenolic compounds
- Contains potassium
- Contains theophylline
- Inhibits reabsorption of Na+ and increases glomerular filtration rate
- Only modest effects
SE of dandelion
- Generally considered safe
- Rare reports of upset stomach and diarrhea and some people are allergic to the plant
- People with an inflamed or infected gallbladder or blocked bile ducts, should avoid using dandelion
- Could cause similar effects as conventional diuretics (i.e. dehydration)
What are the 7 Gut Check Claims ?
1) Causes weight loss of 2 lbs or more a week for a month or more without dieting or exercise
2) Causes substantial weight loss no matter what or how much the consumer eats
3) Causes permanent weight loss even after the consumer stops using product
4) Blocks absorption of fat or calories to enable consumers to lose substantial weight
5) Safety enables consumers to lose more than 3 lbs per week for more than 4 weeks
6) Causes substantial weight loss for all users
7) Causes substantial weight loss by wearing a product on the body or rubbing it into the skin
