Metabolic Availability of Lysine From Barley in Young Adult Men

Each subjects will receive each of up to 10 experimental diets for the Barley Study (4 reference protein diets providing, 3 Barley diets using dry cooking method, and 3 Barley diets using moist heat cooking method) in random order over a series of up to 10 experimental periods. The reference protein diet will be patterned after the AA pattern of egg protein using crystalline AA as the protein source. Three of the 4 lysine levels will be replaced by lysine provided in Barley each cooked using two different cooking methods ( dry and moist-heat).Each experiment will be conducted over 3 days.

Adaptation days:

During days 1 and 2 the subjects will be adapted to the level of lysine being studied, consuming the same diet as they will receive on day 3 (IAAO study day). The adaptation diet will be consumed as 4 equal meals.Meals will be divided into 4 equal parts to be spread evenly throughout the day and consumed in their usual environment on their usual activities of daily living.

IAAO study day/isotope delivery and sample collection day:

On the oxidation study day 3, following a 12-h overnight fast, subjects will come to the Hospital for Sick Children, Toronto, ON for a period of 5.5 h. On the oxidation study day, the diet is consumed as 9 iso-nitrogenous and iso-energetic hourly meals. Between meals, subjects are allowed to rest on bed, watch television or use a computer. Study days for each participant will be separated by ≥ 1 week. For the duration of all experiments, subjects will consume a daily multivitamin (Centrum Forte, Whitehall Robins) and 500 mg choline supplement (Nature's Way or equivalent), to ensure adequate vitamin intake. The multi vitamin supplement is provided to ensure that no vitamin cofactors are limiting in the diet which could alter metabolic pathways and functioning.

Inclusion criteria

• Male, age 18 - 40 years, Healthy with no known clinical condition which would affect protein or AA metabolism, ex. Diabetes,
• Stable Body Weight (±0 to 5lb weight gain or loss in the last 3 months)
• Not on any medications that could affect protein or amino acid metabolism e.g. steroids.

Exclusion criteria

• Unwillingness to participate or unable to tolerate the diet
• Recent history of weight loss within the last 3 months or on a weight reducing diet Inability to tolerate study diets (ex. Allergy to ingredients).