The Effect of Combinatorial Nutritional Supplementation on Immune Function in Healthy Older Adults

Vitamins C and D and the mineral zinc are each considered immune modulating micronutrients,
but their specific effects on the immune system, especially when used in combination, is
relatively unknown. Deficiency in each of these micronutrients is frequently observed in
aging adults and may contribute to age-related declines in immune status. Based on prior
published studies, the investigators hypothesize that supplementation of older adults with a
combination of vitamin C, vitamin D, and zinc will increase the innate ability of neutrophils
to kill invading bacteria through a variety of mechanisms, including increased phagocytosis,
antimicrobial peptide expression and changes in reactive oxygen species (ROS) production.

Therefore, this study is designed to investigate the effects of Redoxon VI, a supplement
consisting of a combination of vitamin C, vitamin D, and zinc on functional markers of the
immune system of healthy, older adults when compared to a matched placebo. To accomplish
this, the investigators will recruit 40 healthy adults between the ages of 60 and 75 and
randomize them to either Redoxon VI or an identical, inactive placebo control supplement to
be taken twice a day for 12 weeks.

Since neutrophil-mediated killing is a crucial defense against Staphylococcus aureus
infection that declines with age, it will serve as a primary outcome in this study. Using
blood collected from individuals before and after supplementation, the investigators will
measure the ability of neutrophils to clear S. aureus cells, and compare the killing activity
in those individuals receiving the vitamin and mineral supplement to those receiving the
placebo. The investigators will confirm these changes in immune cell function by also
measuring phagocytic activity in neutrophils, as well as their ability to produce ROS.

As secondary measures of immune function, the investigators will also determine circulating
levels of neutrophils, monocytes and lymphocytes, measure cathelicidin antimicrobial peptide
(also known as hCAP18/LL-37) levels, and determine changes in circulating levels of
inflammatory cytokines.

Based on previous studies, the investigators expect that any increase in functional immune
status will correspond to changes in vitamins C, D and zinc status in these individuals. The
investigators expect the results from this study to provide the foundation for future studies
investigating combinations of supplements on immune function and more extensive studies using
these micronutrients to restore declines in immune function observed in older adults.

Inclusion Criteria:

- Serum vitamin D level 25-50 nmol/L (10-20 ng/ml), inclusive

- Willing to limit intake of salmon, herring and sardines to one 4-ounce serving per
week for 3 weeks prior to and throughout the study.

- Willing to limit intake of oysters, shellfish, liver, beef, lamb and poultry dark meat
to one 4-ounce serving per week for 3 weeks prior to and throughout the study.

- Willing to limit intake of citrus fruits and citrus fruit juices to 2 servings per day
during the study for 3 weeks prior to and throughout the study.

- Willing to stop taking multivitamins, supplements containing zinc, vitamins C and D,
and food/beverage products supplemented with zinc and vitamins C and D for 3 weeks
prior to and throughout the study.

Exclusion Criteria:

- Usual dietary intake of zinc >15 mg/day (as determined in Telephone Screening Script)

- Tobacco use, including e-cigarettes, or smoking of any substance (e.g. cannabis) in
the past three months or plans to smoke during the study.

- Have undergone a surgical procedure within the past two months or expect a surgical
procedure in the next four months.

- Regularly consume more than two alcoholic drinks a day.

- Have participated in another clinical study within the past two months.

- Undergoing UV therapy (e.g. treatment for skin conditions such as psoriasis) or UV
tanning.

- Have a significant acute or chronic illness such as cardiovascular disease, kidney or
liver disease, diabetes, thyroid or parathyroid disorder, history of cancer less than
five years.

- Have had bariatric surgery (e.g. gastric bypass, gastric banding, sleeve gastrectomy,
etc.), other gastrointestinal procedure (e.g. cholecystectomy) or disorders (e.g.
Crohn's disease, celiac disease, ulcerative colitis)

- Stage II hypertension (either systolic blood pressure > 159 mm Hg or diastolic blood
pressure > 99 mm Hg)

- BMI < 18.5 or > 29.9

- Diagnosis of hypervitaminosis A, hypervitaminosis D, or hypercalcemia

- Have received an organ or tissue transplant

- Have eczema, atopic dermatitis, or psoriasis

- Have or have had allergy to medications or foods, seasonal allergies or allergic
asthma after age 18 (childhood asthma/allergies not exclusionary)

- Diagnosis of an autoimmune disorder (e.g. lupus, rheumatoid arthritis, multiple
sclerosis, etc.) or HIV positive status.

- Currently taking or using any of the following medications:

- Topical medications containing retinoids

- Desferioxamine

- Disulfiram

- Warfarin

- Vitamin D analogs

- Vitamin A analogs

- Cholestyramine

- Orlistat

- Mineral oil (oral intake)

- Thiazide diuretics

- Calcium channel blockers

- Phenobarbital or phenytoin or other anticonvulsants

- Estrogen replacement therapy

- Leukotriene receptor antagonists

- Immunosuppressant/anti-rejection drugs

- Oral corticosteroids