Yes, and very meaningful. The plasticity of the immune system doesn't disappear because you came late. Research shows that people who begin systematic exercise at sixty see considerable immune function improvement within half a year. Late is better than not coming at all.

The shingles vaccine (especially recombinant subunit vaccine Shingrix) has over ninety percent protection efficacy for people over fifty — very effective. Getting vaccinated dramatically reduces disease risk, and even if it occurs, symptoms and sequelae are much milder. Strongly recommended for those over fifty.

Current human randomized controlled trial evidence is very limited. NMN and resveratrol have some positive signals in animal experiments, but translation to human immune function indicators hasn't been sufficiently verified. Before the basics of sleep, exercise, and diet are established, the space for supplements is very limited. This isn't saying they're completely useless, but they can't replace the basics.

The most commonly used indicators are serum high-sensitivity CRP (hs-CRP) and IL-6. Routine health checks may not include hs-CRP, but you can proactively request it. If you have metabolic syndrome, obesity, chronic sleep deprivation, or chronic stress, including this test in annual health checks is recommended.

This is a common misjudgment. Chronic stress's immune damage often doesn't manifest as 'getting sick easily' in early stages — it occurs in invisible ways like elevated inflammation markers, declining NK cell activity, and accelerated immune cell aging. Feeling well doesn't mean the immune system is working well.