None listed
Conditions
Brief summary
The proposed project will investigate whether a methionine restricted diet is a feasible nutritional regimen for healthy ageing in a healthy population. This project will consist of 2 diets: a methionine restricted diet and a standard western diet. As methionine content tends to be higher in flesh foods, the methionine restricted diet will be predominantly plant based. The proposed project will utilise a randomised cross-over design so that each volunteer consumes both diets. Healthy volunteers (n=20) with no history of cancer will be recruited. The proposed project will measure the effect of a methionine restricted diet on biomarkers of health and ageing. Blood will be collected from the volunteers at specific time points and analysed for biomarkers of ageing; lymphocytes will be isolated to measure genome integrity and serum will be utilised in vitro to determine rate of growth of established cancer cell lines.
Interventions
Methionine restricted diet: As methionine content tends to be high in flesh foods, the methionine restricted diet will contain fewer meat options. The composition and energy intake of the methionine restricted diet will reflect that of the standard Western diet (~50% carbohydrate, ~15% protein and ~35% fat; 8400 KJ daily energy intake). To obtain a desirable amount of protein in the methionine restricted diet, foods that are higher in protein but lower in methionine will be chosen. For example,
Methionine restricted diet: As methionine content tends to be high in flesh foods, the methionine restricted diet will contain fewer meat options. The composition and energy intake of the methionine restricted diet will reflect that of the standard Western diet (~50% carbohydrate, ~15% protein and ~35% fat; 8400 KJ daily energy intake). To obtain a desirable amount of protein in the methionine restricted diet, foods that are higher in protein but lower in methionine will be chosen. For example, lentils contain roughly 25% more protein and less than half the methionine content per 100 g than beef. This study aims to restrict methionine as much as is practicable, approximately in the range of at least 40% but no more than 80% with a view to achieving 60% on average methionine restriction relative to the standard Western diet. This dietary intervention will run for 4 weeks. CSIRO will be providing a daily main meal during the intervention and guidelines for appropriate breakfast and lunch meals. There will be a 4 week washout between dietary interventions.
Sponsors
CSIRO
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Prevention
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
50 Years to 70 Years
Healthy volunteers
Yes
Inclusion criteria
- Male or Female - Aged 50-70 - Healthy with no history of cancer - Body mass index in the healthy range (BMI): 18.5-27
Exclusion criteria
- History of smoking - Currently on medication/dietary supplements which may impact methionine, folate and B vitamin content in the blood - Current vegetarians/vegans
Outcome results
None listed