David raubenheimer protein_and_the_burden_of_obesity_in_australia
1. The Silent Manipulator: Protein and the Burden
of Obesity in Australia
1
David Raubenheimer
Leonard P Ullman Chair of Nutritional Ecology
Faculty of Vet Science | School of Biological Science | Charles Perkins Centre
2. Nutritional Ecology is âŚ.
⢠Ecological / evolutionary approach to nutrition
- focus on how nutrition mediates the relationship between animal & environment
- to determine health and wellbeing
Animal Biology
Environment
NUTRITION
health
lifespan
reproduction
etc.
7. ⢠How does the human appetite respond to dietary imbalance?
2) Human appetite
?
8. - humans prioritise P over F + C
⢠Meta analysis: 26 published trials
model
Gosby et al. (2013) Obesity reviews.
⢠Experiments in Oxford, Sydney & Jamaica
prioritiseP
9. ⢠Can protein prioritisation help understand the global rise in obesity?
Source:AustralianInstituteofHealthandWelfare
3) Obesity
Australia 1980-2008
10. Protein
Carbohydrate+fat
14% P12.5% P
(1.5%)
- a small change in % P in foods will result in a large change in the
amount Carbs + Fat eaten
- for example, a 1.5% decrease in % P
14% increase in C + F eaten
-> Called the âProtein Leverage Hypothesisâ (PLH)
- could this help explain the obesity
epidemic?
⢠Very likely:
11. 0 10 20 30 40 50 60
0
20
40
60
80
Energy intake (kj/day)
Protein (% kj)
Fat(%kj)
5000
6000
7000
8000
9000
10000
11000
[0]
[20]
[40][60]
(10:30:60)
1) Energy intake increases with decreasing %P
Two predictions of PLH
- Yes!
12. Prediction 2) Dietary % P has decreased with the rise in obesity
Data:FAOSTAT2010
- e.g. Australia
year
Protein(%energy)
- Yes!
15. 0 10 20 30 40
0
20
40
60
80
100
Protein g/100g
Fat+carbohydrateg/100g
0.6
0.8
1
1.2
1.4
1.6
1.82
2.2
1) Protein is more expensive than fats and carbs
$/100g
Brooks et al. (2009) Obesity reviews.
Three predictions
- 106 supermarket foods
- price increases with % P
- not with fats & carbs
⢠Test
⢠Result
- compared the separate
contributions to the price
of each g of Pro, Fat and Car
- suggests an economic incentive
to eat low P foods
⢠Conclude
cheap expensive
cheap
16. Prediction 2). Low SES groups eat low-protein diets
- 14 diet surveys of low SES
indigenous Australian communities
- most have low % P relative
to recommended range
⢠Aboriginal study
⢠Compared with Australian
recommendations (AMDR)
[With Aboriginal Nutrition Project Node]
17. Prediction 3). Low protein diets are associated with high energy intake
- yes!