Aminostatic hypothesis

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In 1956, Mellinkoff proposed the aminostatic hypothesis, stimulated by the observation that when normal individuals ingest protein, appetite diminishes as the serum amino acid concentration rises and vice versa. He believed this was due to a satiety centre in the brain, sensitive to serum amino acids levels, that caused a suppression of hunger once the serum levels reached a certain point.Ashleigh Fraser 15:34, 25 October 2011 (UTC)

Experimental Evidence

-experimental evidence has agreed with the aminostatic hypothesisAshleigh Fraser 15:34, 25 October 2011 (UTC)

-they have found that high protein diets act on satiety and thermogenesisAshleigh Fraser 15:34, 25 October 2011 (UTC)

Science behind the theory

© Image: Ashleigh Fraser
Indirect Pathways

Amino acids obtained from the diet generate postprandial signals which have an affect on food intake. The signals activate specific brain areas in one of two ways:
1) Indirectly though vagus-mediated pathways
2) Directly after their release into the peripheral blood
The indirect and direct pathways are summarised in the figures below.Ashleigh Fraser 16:16, 25 October 2011 (UTC)

© Image: Ashleigh Fraser
Direct Pathway.

Use as a method of weight loss

Obesity is everywhere. Around 33% of American adults and 17% of children are obese (A). In the UK, the statistics are not looking much brighter with 25% of adults and 10% of children showing signs of obesity. It has been proposed in the UK that 60% of men, 50% of women and 25% of children will become obese by 2050 if no preventative measures are taken (B). This growing prevalence of obesity needs a solution. Many hypotheses regarding different weight loss diets have been proposed. So how can the aminostatic hypothesis be used for treatment? Perhaps a high protein diet is the answer. Lisa Robertson 15:37, 25 October 2011 (UTC)

• What does the diet consist of? Benefits of high protein diet with supporting evidence (2,3,7,8,10). Animal/veg protein best? Lisa Robertson 15:37, 25 October 2011 (UTC)

Limitations

-are there any downsides to a high protein diet?

-appetite is a feeling so different participants in experiments may report it differently and so results may not be completely accurateAshleigh Fraser 15:34, 25 October 2011 (UTC)

• Consequent effects on renal function. Usually low carb diet is needed along with HP diet to gain full beneficial effects (subjects more satisfied).

Conclusion

• Future studies, maybe more into long term effects of diet. Any drugs that may interact with pathways? Lisa Robertson 15:44, 25 October 2011 (UTC)

References

(A)Centers for Disease Control and Prevention. (2011). U.S Obesity Trends. Available: http://www.cdc.gov/obesity/data/trends.html. Last accessed 25th Oct 2011.

(B)Department of Health. (2011). Obesity. Available: http://www.dh.gov.uk/en/Publichealth/Obesity/index.htm. Last accessed 25th Oct 2011.