…and other items from this week’s health science news:

Help others, to help your brain

We’ll get straight to it: spending about 2–4 hours a week helping people outside your household is associated with a roughly 15%–20% slower rate of age-related cognitive decline over time.

Notably, both formal volunteering and informal helping show comparable cognitive benefits, so it doesn’t have to be anything fancy, it just has to be helping people.

What seems most important is not the amount of time itself so much as the consistency—moderate, sustained engagement delivers the strongest and most consistent benefits, while heavier time commitments are not required. This shows itself to be particularly true as time goes on, since benefits accumulate year after year when helping becomes a stable routine, whereas withdrawing from helping is linked to worse cognitive function.

You may be wondering about the science behind this, and it was quite a big study: the analysis followed 31,303 people aged 51 and older for up to two decades, and yes, the results still held after accounting for wealth, education, and physical and mental health, suggesting the association is not explained by these factors alone.

As for how this happens, the researchers hypothesize that helping supports brain health by reducing stress-related inflammation and strengthening social connections that provide cognitive and emotional support.

So, how about you? If your first thought wasn’t “Oh, like my [thing that you regularly do and have consistently done over time]”, then now’s a great time to get started!

Read in full: Helping others for a few hours a week may slow brain aging

Related: 9 Little Habits To Have A Better Day

Whooping cough on the rise again in the US

The news is not good on this one. Whooping cough cases rose sixfold in 2024, and remain high in 2025, with more than 26,600 US cases reported by December 2025, over 4x the total for all of 2023.

Some parts of the US are doing worse than others, with some states are seeing levels not recorded for decades, including Oregon exceeding its 1950 annual record and Kentucky reporting three infant deaths in 2025 after none since 2018.

Unfortunately, public awareness is not strong: 30% of US adults do not know that pertussis is the same as whooping cough, and 35% do not know that a preventive vaccine exists. On which note, the CDC recommends the DTaP vaccine for young children in a 5-dose series, and Tdap for preteens, adults, and pregnant women during weeks 27–36 of pregnancy.

Nor do most know what the symptoms are: while 77% recognize coughing fits as a symptom, fewer identify low-grade fever, vomiting after coughing, or a runny nose.

So, to set yourself ahead of the crowd…

Read in full: Whooping cough cases rise sharply across the United States

Related: Vaccine Mythbusting

Mitochondria and mental health

Researchers (Dr. Lydia Wu-Chung et al.) tested the hypothesis that psychological and social experiences—such as stress, isolation, and trauma—affect mental health by altering mitochondrial function in brain cells. the proposed mechanism is that mitochondria act as a bridge between psychosocial experiences and physiological brain changes, helping explain how stress “gets under the skin.”

What they found was that altered mitochondrial function is associated with anxiety, depression, post-traumatic stress disorder, Alzheimer’s disease, cardiovascular disease, diabetes, and certain cancers. That’s a lot!

This is not too surprising, though, as the brain’s high energy demand makes it especially sensitive to mitochondrial inefficiency, which can impair neurotransmission, plasticity, mood regulation, and memory.

The relationship appears to be bidirectional also, as chronic stress can reduce mitochondrial efficiency over time, helping explain fatigue, cognitive difficulties, and mood disturbances seen in long-term stress.

Based on this research, she says that improving mitochondrial health may be a good option for many people to increase energy availability, reduce inflammation, and improve brain signaling.

As for how to do that? Endurance and aerobic exercise show the strongest and most consistent evidence for enhancing mitochondrial number and enzyme activity, while mindfulness programs and psychotherapy have shown changes in mitochondrial activity or number, but evidence for these latter associations is mixed and not always correlated with symptom improvement. So, exercise seems the main way to do it, for best results.

And in terms of things to avoid: social isolation can worsen mitochondrial function by reinforcing low energy, anxiety, and withdrawal, making recovery cycles harder to break.

So, maybe do that exercising with others, if you can!

Read in full: Mitochondria may be missing link between mental health and brain function

Related: 7 Ways To Boost Mitochondrial Health To Fight Disease

Take care!