Feeding Trial to Determine How Combinations of Different Dietary Bioactive Ingredients Influence High Density Lipoprotein (HDL) Metabolism

This study a partial randomized crossover study designed to determine how consumption of bioactive dietary ingredients in various combinations on three separate test days influences postprandial lipoprotein metabolism in participants with low circulating HDL-cholesterol.

The dietary ingredients include:

Dairy phospholipids(PC700); krill oil (K); lutein (L); and Niacin

Eligible participants will arrive to the University of California Davis (UC Davis), Ragle Human Nutrition Center on the morning of each test day after a 10-12-hr overnight fast. Upon arrival participants will fill out a questionnaire about their dietary and medication intakes and physical activity for the past 72 hours to ensure compliance. Compliant participants' weight and blood pressure will be measured and a fasting blood draw will be taken before participants consume their test meal in the form of a milkshake (control, PC700KL, PC700KL + Niacin). On each test day, participants will be given only this meal and provided with ample supply of bottled water.

Participants will only consume this test meal and water freely for the duration of the test day. Blood will be drawn serially at 2 and 4 hours postprandially. Participants will also be asked to provide 3 urine samples throughout the study: before and 2, and 4 hours after consumption of the milkshake. Participants will be tested on two additional separate test days after the first day separated by a two-week washout. The first two test days will be randomized, however the third test day will always contain niacin in order to require participants remain at Ragle for the first two hours of the study to monitor niacin flushing reactions. Participants have the option of participating in two out of three of the test days if they wish to exclude themselves from the niacin test day.

Inclusion criteria

• Age 18-65 years
• Plasma HDL cholesterol (Less than 50 mg/dL)

Exclusion criteria

• History of gastrointestinal disorders like Crohns disease, colitis, irritable bowel syndrome
• History of cardiovascular events: stroke, heart attack, cardiac arrhythmia
• History of peptic ulcers, gastritis
• History of gout
• History of being under care of any psychiatric conditions (schizophrenia and depression associated with response to niacin)
• Cancer
• Type 1 or 2 diabetes
• Known presence of significant metabolic disease which could impact results of study (hepatic, renal disease)
• Low blood pressure (defined as 3 consecutive readings below 100/60 mmHg at screening)
• Self report skin sensitivities; self report to rash easily
• Self report to hot flashes currently experience due to menopause
• Hypersensitivity to niacin
• Muscle disorders such as myasthenia gravis
• Pending surgery within the next 3 months
• Known allergy to study food (shellfish, fish, nut, soy)
• Known intolerance to study food (lactose intolerance)
• More than 1 serving of fish per week
• Intake of anti-inflammatory supplemental fish, krill, borage, flax, and primrose seed oils within the last 12 weeks
• Intake of dietary supplements consisting of concentrated soy isoflavones, resveratrol, other dietary polyphenols identified as modulators of lipids within the last 12 weeks
• Intake of more than 20 mg of lutein and zeaxanthin per week
• Intake of nicotinic acid (niacin) within the last 12 weeks
• Intake of anti-coagulants, blood pressure or heart medications within the last 12 weeks
• Plan to become pregnant in next 6 months
• Recent initiation (past 4 weeks) of exercise program
• Use of tobacco products
• Excessive alcohol consumption (2 drinks/day for men and 1 drink/day for women)