Between Saturdays
This week: how collagen strengthens bone, how native collagen eases joint pain, how vitamin D guards against autoimmune disease, and how vitamins C quietly support mental vitality and calm.
The body ages in layers from bones to joints to nerves. What we call “aging” is really the slow unraveling of structure and signaling, a process shaped as much by nutrition as by time.
This week’s four studies explore how specific nutrients such as collagen, vitamin D, vitamin C, and vitamin B6 reinforce that structure: building bone, protecting cartilage, regulating immunity, and balancing the brain’s chemistry of calm.
Caught My Eye…
Collagen Peptides and Bone Strength
In a year-long randomized, double blind, placebo controlled trial published in Nutrients (2018), 131 postmenopausal women with low bone mineral density took 5 g/day of specific collagen peptides or a placebo. After 12 months, the collagen group showed significant increases in bone mineral density at both the lumbar spine and femoral neck compared with placebo.
Markers of bone formation, including P1NP, rose significantly signaling active collagen synthesis and bone rebuilding. The treatment was well tolerated, with no safety issues reported.
Researchers concluded that collagen peptides may stimulate osteoblast activity, improving bone microarchitecture and mineral deposition effectively giving the body the raw material and signal to rebuild its own framework.
Native Collagen and Joint Health
A 2022 randomized, double blind trial in the Journal of Experimental Orthopaedics enrolled 101 adults with knee osteoarthritis and compared three interventions: native type II collagen, glucosamine+chondroitin, or placebo over 12 weeks.
By week four, participants taking native collagen reported significant improvements in pain and physical function, measured by the WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index). The benefits continued to grow through week 12, with similar or better results than the glucosamine-chondroitin group.
Importantly, collagen was well tolerated, with no increase in adverse events.
The findings support a growing body of evidence that undedenatured type II collagen helps retrain immune tolerance to joint cartilage, reducing inflammation and pain sensitivity, not by masking symptoms, but by changing how the body responds to wear and tear.
Vitamin D and Autoimmune Defense
The VITAL trial, published in the BMJ (2022), followed 25,871 U.S. adults (men ≥50, women ≥55) for over five years to test whether vitamin D₃ (2,000 IU/day) and marine omega 3s could prevent new autoimmune diseases.
After 5.3 years, those taking vitamin D₃ had a 22% lower incidence of autoimmune diseases compared with placebo (Hazard Ratio = 0.78, 95% CI 0.61–0.99). The protective effect became stronger after the second year of supplementation, suggesting that steady, long-term intake helps modulate immune balance.
Vitamin D acts as a hormone for immune regulation, dampening overactive responses while enhancing innate defense. This study reframes vitamin D not only as a bone nutrient but as a broad immunological stabilizer quietly reducing the odds of conditions like rheumatoid arthritis, lupus, and psoriasis before they start.
Vitamin C and Mental Vitality
A 2022 randomized, double blind trial in the European Journal of Nutrition looked at how restoring vitamin C status affects the mind as much as the body. Researchers recruited healthy young adults whose blood vitamin C levels were low, common in modern diets heavy on processed food and light on fresh produce and gave them 1,000 mg of vitamin C daily (split into two 500 mg doses) for four weeks.
By the end of the study, participants receiving vitamin C showed clear improvements in attention, concentration, and motivation, performing better on the Stroop test, a measure of cognitive control and mental flexibility. They also reported less fatigue and higher overall “mental vitality.”
The findings point to an often overlooked role for vitamin C beyond immunity or skin health: it supports neurotransmitter synthesis and antioxidant protection inside the brain, helping neurons fire efficiently under stress. For anyone who drifts through the day feeling mentally foggy or unmotivated, a steady intake of fruits, vegetables, or a small supplement might be a surprisingly effective cognitive tune-up.
Detailed Readings
Specific Collagen Peptides Improve Bone Mineral Density and Bone Markers in Postmenopausal Women
Vitamin C supplements promotes mental vitality
Vitamin D and marine omega 3 fatty acid supplementation and incident autoimmune disease