None listed
Conditions
Brief summary
Proteins are essential components of the human diet as sources of energy and amino acids. As we age the consumption of nutrient-rich sources of protein such as meat is reduced in some people due to changes in oral health, decreased appetite and for social and economic reasons. Hydrolysing (partially digesting) proteins into a powder is one way of increasing access to, digestion and absorption of nutrient-rich proteins. The purpose of this project is to evaluate the absorption and utilisation of nitrogen from hydrolysed meat protein. To do this we will enrich the nitrogen that occurs naturally in lamb meat with a marker (stable isotope of nitrogen known as 15nitrogen or 15N) so that we can trace this source of nitrogen in the body. We will do this because nitrogen present in the gastrointestinal tract can originate from inside the body (mucus, cells, digestive enzymes and secretions) and from outside the body (from food). The “marked” meat will be hydrolysed into a powder, incorporated into a soup as the sole source of protein and fed to participants. We will then detect the amount of nitrogen that is digested, absorbed and used metabolically from the soup via the marker. Participants will be required to consume a diet containing the recommended daily intake of protein for seven days to standardise their protein intake. On day eight, fasted participants will be asked into our nutrition laboratory where they will consume a soup containing the hydrolysed protein. Blood and urine samples will be collected for eight hours following the meal. Analysis of these samples will tell us how much nitrogen from the hydrolysate has been transferred into the blood and urine. Calculations performed using this information will determine the utilisation of the hydrolysate.
Interventions
The study is a randomized parallel design metabolic study. The aim is to determine the net postprandial protein utilisation (NPPU) and postprandial biological value (PBV) of a lamb meat protein hydrolysate in older adults and to compare this with the NPPU and PBV of a dairy protein, casein. Dairy proteins are considered the gold standard for protein digestibility and utilisation in the body. The study will be conducted at Massey University in the Human Nutrition Research Unit by Dr Sharon Hen
The study is a randomized parallel design metabolic study. The aim is to determine the net postprandial protein utilisation (NPPU) and postprandial biological value (PBV) of a lamb meat protein hydrolysate in older adults and to compare this with the NPPU and PBV of a dairy protein, casein. Dairy proteins are considered the gold standard for protein digestibility and utilisation in the body. The study will be conducted at Massey University in the Human Nutrition Research Unit by Dr Sharon Henare, physiologist, who has 13 years experience conducting nutrient digestibility and utilisation studies and two registered nurses. The intervention will be one 9-h session following an overnight fast from 10pm to when the participant arrives at the research unit the next morning. Fasting will involve not eating any foods or drinking any liquids. To ensure participants remember to fast a text message reminder will be sent at 9pm. On arrival to the research unit the next morning and before the intervention, participants will be asked whether they ate or drank during the fasting period. Individual participants will be required to consume a single mixed meal that contains 30 g of protein from either 15N-labelled lamb hydrolysate or 15N-labelled casein as the sole source of protein, 15 g of fat from canola oil and 55 g of carbohydrate from maltodextrin mixed in to 400 ml of water. The lamb hydrolysate mixture will be blended with a whisk over heat and served at 60°C. The casein mixture will be blended and served at room temperature. Blood and urine samples will be collected from participants before consuming the meal and then 30, 60, 90, 120,150, 180, 240, 300, 360, 420 and 480 min after the meal for blood and 2, 4, 6 and 8 h after the meal for urine. Analyses will determine where in the body the nitrogen from each protein source is utilised and the data used to calculate NPPU and PBV.
Sponsors
Massey University
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
60 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
60 years of age or older Be in good general health Not vegetarian or vegan Not suffering from any disorders of digestion or taking medication that affects the gut
Exclusion criteria
Have had gastrointestinal surgery or a gastrointestinal disorder Have had or have hepatic or liver disorder Have a urinary tract disorder Have had or have a blood borne disease (example: hepatitis B or C) Have a bleeding or clotting disorder Have had gall bladder surgery Have a bowel disorder Have a cardiac disease (heart disease) Are diabetic Smoke cigarettes Consume more than 2 glasses of wine or 1 pint of beer a day Have allergies to dairy products or eggs Have experienced significant weight loss during the past six months Are taking medications that affect digestion
Outcome results
None listed