A neurologist wrote a piece in SSM Health www.ssmhealth.com (January 2025) emphasising that the brain can form new pathways at any age, and that social puzzling, that is, doing jigsaw puzzles with family or friends, offers even greater benefit than solo puzzling.
Why is that? The answer seems to be quite clear in our association’s creative room, where we have a daily on-going puzzle, open to all of us, and not excluding random visitors, who just have to add “one more piece to the puzzle”.
Another study mentioned in http://www.RealityPathing.com (July 2025) talks about other benefits, on a more personal level. Focusing attention on a puzzle shifts attention away from worries and intrusive thoughts, and the “flow state” can lower cortisol levels and produce a sense of calm.
We love to puzzle together and in the creative room there is space for people to read, knit, write and above all meet and chat. Surely this helps promote a sense of well-being and maybe even slow cognitive decline. We like to think so.
It’s widely accepted that following a balanced diet is one of the best things we can do for our health. But certain foods are more important at different life stages.
During World War Two, the British government introduced a rationing policy that allowed families a weekly allowance. The idea was to allow people to meet their nutritional needs while ensuring food could be distributed equally across the nation.
Sugar was one of the foodstuffs that was rationed. Individuals were allowed around 8oz (227g) of the sweet stuff per week. Much to their chagrin, children under two years old weren’t allocated any, however.
When sugar rationing ended in 1953, average sugar intake of adults doubled. Little did people know at the time, but this would allow scientists in the future a great opportunity to pinpoint the effects of early sugar consumption on our health.
In a 2025 paper, a global team of researchers poured through the medical records of 63,000 people born in the UK between 1951 and 1956 – when sugar rationing was in full force. They found that children who were exposed to less sugar in the womb and for the first 1,000 days of life were 20% less likely to develop cardiovascular disease in later life; 25% less likely to develop heart failure; and 31% less likely to have a stroke than children who were allowed to stuff their mouths with sweets after rationing ended.
It’s probably not a surprise to learn that this strong relationship between sugar intake and health continues after we’re born. Simply put, eating too many sweet sugary snacks is bad for us no matter what age we are.
But with some other foods, the nutritional benefits depend on what stage of your life you happen to be in. Young babies and infants need plenty of the fats present in dairy and whole milk, for example, but such a diet would not be considered so healthy for someone in their 20s and 30s.
According to Federica Amati, a nutritional scientist at Imperial College London in the UK, children’s high energy demands mean they need foods packed with nutrients.
The foods we need as a growing child are not always the ones we need in later life (Credit: Serenity Strull/ BBC)
“In childhood, food is literally building the body and the brain,” says Amati. As well as healthy calories, children also need iron, iodine, and a wide range of vitamins to support immunity, brain development and muscle growth.
This means plenty of fruit and vegetables, wholegrains, beans and lentils, good quality fats including nuts and seeds, and minimal ultra-processed foods.
“From conception through the first 1,000 days and into the school years, children are growing rapidly and laying down most of their future bone mass,” says Amati. “That’s why calcium and vitamin D are priority nutrients at this stage; they’re essential for normal bone development and for achieving a healthy peak bone mass, which reduces the risk of osteoporosis and fractures later in life.”
There’s good evidence that eating the right foods in childhood can benefit health later in life
In practice, Amati says, this means regular sources of calcium – such as milk, yogurt, cheese, calcium-set tofu or fortified plant drinks – and vitamin D, from sun exposure and foods like fish and eggs.
There’s good evidence that eating the right foods in childhood can benefit health later in life. In one 2023 study, researchers looked at the diets of children and compared this to their health as children and young adults. They found that children who met three or more dietary recommendations from the UK’s Eatwell Guide at the age of seven had lower heart disease risk markers at age 24 compared to those who had met none of the requirements.
Teens and 20s
While childhood is an important time, the foods we eat in our teens and 20s can also lay the groundworks for future health. According to Amati, this life stage is when we finish building bones and muscle, and start spending hours studying, working, and socialising – all of which increase nutrient needs.
“Adolescence and early adulthood are another big window of opportunity for nutrition,” says Amati. “In the 20s, growth slows, but it’s still a crucial decade for establishing habits that protect heart and brain health in later life. We see that a lot of the groundwork for cardiovascular disease is already being laid in this age group, even though symptoms appear much later.”
In our teens, the body needs more of several nutrients compared to later adulthood. This includes calcium, vitamin D and iron – which is especially important for those who menstruate. Protein and B vitamins are also important, Amati says.
So what does this diet look like? According to Amati, teens and young adults should follow a largely plant-based diet and avoid ultra-processed foods. So lots of fruit, vegetables, wholegrains, beans, nuts, lentils and seeds. It’s also important to have an adequate amount of protein for every meal, which can also be plant-based, she says.
Studies show that following such a diet doesn’t just benefit the body, it can impact mental health too.
“There’s growing evidence that dietary patterns in adolescence can influence mental health risk – diets high in ultra-processed foods and low in whole plant foods are associated with higher rates of depression and anxiety, while more Mediterranean-style patterns appear protective,” Amati says.
The Mediterranean diet is high in vegetables, legumes, nuts and olive oil, with smaller amounts of fish, dairy and poultry.
Women approaching the menopause should be looking at making changes to their diet in the years ahead, some scientists say (Credit: Serenity Strull/ BBC)
In mid-life, we should be starting to think about optimising our diet for health in later life, according to Elizabeth Williams, professor of human nutrition at the University of Sheffield in the UK.
This is particularly true for women around the age of menopause, “when there is accelerated loss of bone density, sarcopenia [age-related muscle loss] and osteoporosis”, says Williams.
As women move into their 40s and 50s, two big nutritional priorities emerge: heart health and bone and muscle health – Federica Amati
However, this risk can be significantly offset by following a good diet. For instance, in a recent population study, researchers looked at the diet and health of more than 100,000 US men and women aged at least 39. They found that a healthy diet consisting of fruits, vegetables, whole grains, unsaturated fats, nuts, legumes and low-fat dairy products was strongly associated with healthy ageing (which they define as living to at least 70 with no chronic disease, and good cognitive and physical function and mental health).
“As women move into their 40s and 50s, two big nutritional priorities emerge: heart health and bone and muscle health,” Amati says. “The menopausal transition is associated with a sharp rise in cardiovascular risk, partly because the loss of oestrogen affects blood lipids, blood vessels and body fat distribution.”
Omega 3 fats – especially the types found in oily fish such as mackerel and salmon – help because they lower the risk factors for heart disease, Amati says, and have anti-inflammatory effects.
Meanwhile Amati recommends a slight increase in protein intake to counter the effects of muscle-mass loss, and following a Mediterranean-style diet for better cardiometabolic health – and possibly gut health and mental health too.
Ultimately, she says, it’s important to aim for a varied, plant-rich, Mediterranean-style diet with sufficient protein, calcium, vitamin D and omega-3s that supports heart, bone and brain health, while limiting ultra-processed foods.
Later life
As we get older, our body composition changes and our energy requirements decline, so we need to consume less calories. However we still need to ensure that we get enough nutrients to maintain bone and muscle strength.
According to Williams, the two main nutrients we should focus on in old age are calcium and vitamin D. Older people who don’t get enough calcium or vitamin D have an increased risk of osteoporosis and fragility fractures. Calcium is found in milk and fortified alternative drinks, hard cheese, yoghurt, sardines, tofu and spinach. Vitamin D-rich foods include oily fish, egg yolk and fortified foods.
Eating enough quality protein is also really important as we age, says Jane Murphy, dietician and co-lead of the Ageing and Dementia Research Centre at Bournemouth University in the UK.
“As we age, our form and functions deteriorate, we lose muscle mass and strength, and need protein to prevent sarcopenia,” she says.
But to ensure our bodies use it properly, protein should be one part of a balanced diet that includes carbohydrates, good quality fats (such as unsaturated fats including olive oil, avocados, nuts and oily fish), and vitamins and minerals, Murphy adds.
People living to 100 seem to be defying many other aspects of ageing common to other people. They have a diverse microbiome that looks different to other older people’s – Mary Ni Lochlainn
As we get older, our microbiomes also shift, characterised by a loss of beneficial bacteria such as Firmicutes and Bifidobacterium, alongside an increase in potentially harmful species like Clostridium. This imbalance is associated with several health conditions, such as Alzheimer’s, stroke and heart disease.
While researchers don’t yet fully understand the gut microbiome in relation to every different disease process, we can learn a lot from centenarians, according to Mary Ni Lochlainn, clinical lecturer in geriatric medicine at King’s College London in the UK.
Generally, there isn’t a definition of healthy or unhealthy gut bacteria, as it’s more about having an equilibrium of microbes that work together to promote health. However, a few specific bacterial species have been identified, such as Faecalibacterium prausnitzii, that seem to be protective of health.
People who are ageing well are much more likely have F. prausnitzii, Ni Lochlainn says, but while researchers have established that it has protective, positive qualities, they don’t fully understand how it works. If you want to encourage F. prausnitzii to live in your gut, a diet high in fibre and polyphenols (abundant in fruit and vegetables) is the best way to go.
Finally, some supplements may be beneficial in later life. Ni Lochlainn’s research shows that prebiotic supplements – natural compounds which encourage the growth of beneficial microorganisms – can improve cognition over a 12-week period in older adults. Ni Lochlainn’s prebiotics contain inulin, a type of dietary fibre, and fructo-oligosaccharides – sugars found in plants. Other research suggests that elderly people – especially care home residents may benefit from vitamin D supplements.
Would I use a nasal saline spray or rinse to help treatCovid, flu, and other nasty respiratory illnesses? Absolutely. I would.
What about to help prevent those infections from taking hold in the first place? Sure. I would. I have.
I think we are leaving a cheap and easy way to help prevent/treat respiratory infections on the table. A missed opportunity to help prevent flu and Covid and RSV and the rest. It is one of the few archaic medical practices that has survived the scrutiny of evidence-based medicine. You know, nasal saline — sprays, rinses, and some techniques in between?
It’s unglamorous, unprofitable, and not so buzzworthy. Nerdy perhaps. But the use of nasal saline irrigation as a medical treatment dates back over 5,000 years to the ancient Hindu Ayurvedic tradition, where the practice called jala-neti was performed daily for personal hygiene. Ancient Greek and Roman physicians also developed nasal lavage devices, showing that multiple civilizations independently recognized the benefits of washing nasal passages with salty water. After being documented in medical journals like The Lancet in 1902, the practice surged in Western medicine, especially as those intrepid physicians had few weapons of worth against infections. Modern research validates what ancient practitioners knew – that saline irrigation effectively removes pathogens and debris while creating an inhospitable environment for viruses
As flu season, the predictable holiday Covid wave, RSV season, and the rest of the miserable, pointless viruses bear down upon us, many ask about simple interventions that might help prevent or treat illnesses. We have good hygiene, vaccines, ventilation, and sometimes antivirals. But today’s review will examine the current evidence for not overlooking or underestimating nasal saline in terms of:
preventing respiratory illnesses
potential as post-exposure prophylaxis
established role in treating viral infections.
Understanding the biological rationale
The nasal cavity serves as the primary portal of entry for respiratory viruses including SARS-CoV-2 and influenza. Nasal ciliated epithelial cells are the initial targets for viral entry, and after replication, viral particles are released at the cells’ apical surface (facing into the air passages), allowing progressive infection and spread to the deeper airways. The concept of micro-aspiration—whereby virus, mucus, and inflammatory junk from the oral and nasal cavities spread to the lower respiratory tract—is increasingly recognized as a key mechanism driving progression from upper to lower respiratory tract disease.
Based on current evidence, including recent research accelerated by the Covid pandemic, the mechanisms by which nasal saline irrigation reduces viral infections and aids treatment can be categorized into physical clearance, enhancement of innate immunity, and direct intracellular antiviral effects.
1. Physical clearance & mechanical removal
The most immediate mechanism is simply the rinsing effect, which physically reduces the burden of pathogens and inflammatory byproducts. Think itsy bitsy spider.
Viral load reduction: Saline irrigation mechanically flushes viral particles from the nasal cavity and nasopharynx, reducing the viral load available to infect local cells or be aspirated into the lungs.
Removal of inflammatory junk: Irrigation helps removes local inflammatory cytokines (e.g., IL-6, IL-8), histamine, leukotrienes, and prostaglandins from the nasal mucosa. This reduction in chemical mediators helps alleviate congestion and local inflammation.
Bioaerosol hygroscopic growth: Any fluid engineers reading? Apparently saline alters the physics of exhaled droplets. The addition of saline causes respiratory droplets to grow via hygroscopic absorption of water. These larger droplets deposit in the upper airways (where they can be cleared) rather than remaining as fine aerosols that penetrate deep into the lungs.
2. Enhancement of mucociliary clearance
Nasal saline can help the function of the mucociliary transport system, the upper respiratory tract’s primary defense mechanism and broom.
Ciliary beat frequency: Saline irrigation improves the frequency of ciliary beating, which is often impaired during viral infections.
Mucus thinning: Viral infections often produce thick, viscous mucus that traps bacteria and viruses but is difficult to clear. HOCCKKK! Eww, sorry. Saline hydrates the mucus layer, reducing viscosity and elasticity, which facilitates more efficient transport of pathogen-laden mucus toward the nasopharynx to be swallowed and obliterated by stomach acid.
Recent research, particularly from the ELVIS (Edinburgh and Lothians Viral Intervention Study) trials, highlights a biochemical mechanism where saline fuels the body’s own antimicrobial production. And yes, there is a bunch of Scottish nasal saline trials under the acronym ELVIS. Combining Scottish anything with Elvis something is the world’s most reliable way to make something cool.
Generation of hypochlorous acid: Nasal epithelial cells and innate immune cells (like neutrophils) possess peroxidase enzymes. These utilize intracellular chloride ions provided by the saline solution to convert hydrogen peroxide into hypochlorous acid. Viruses hate to be doused in such acid.
Virucidal action: Hypochlorous acid is a potent oxidizing agent (similar to the active ingredient in bleach) that has broad-spectrum antiviral activity. By increasing the availability of the chloride substrate, saline irrigation effectively supercharges this innate intracellular defense mechanism, leading to the direct inactivation of viral particles.
4. Intracellular & molecular inhibition
Studies investigating SARS-CoV-2 specifically have identified novel molecular pathways by which saline—particularly at hypertonic concentrations—interferes with viral life cycles.
Inhibition of furin protease: The enzyme furin is a host protease that many coronaviruses (including SARS-CoV-2) hijack to cleave their spike proteins, a necessary step for cell entry and fusion. Hypertonic saline has been shown to inhibit furin activity, effectively locking the virus out of host cells.
Membrane depolarization: When there’s a lot of salt outside cells, it opens special channels that change the electrical charge across the cell membrane. This puts the cell into a “low energy mode” where it has less available fuel to power its normal activities. While this doesn’t harm the cell itself, it creates conditions that make it much harder for viruses to replicate, since viral reproduction requires a lot of energy from the host cell. Essentially, the salt water creates an environment where viruses can’t as effectively hijack the cell’s machinery to make copies of themselves.
Inhibition of viral replication:In vitro studies have observed a dose-dependent reduction in viral replication, with isotonic saline (0.9%) reducing replication by ~50% and hypertonic saline (1.5%) achieving near 100% inhibition in some models.
Clinical applications and evidence
Alright, we made it through the hard/fun scientific part. Now what about the family doctor stuff, in which we care more about patient outcomes and the zoomed out big picture?
Prevention of infection and post-exposure prophylaxis
Nasal saline can reduce your chance of getting sick, but it is hard to pin down by just how much.
The Immune Defence trial, a large multicenter randomized controlled trial conducted in UK primary care and published in The Lancet, enrolled 14,000 adults at increased risk for respiratory illness. People were randomized to isotonic saline nasal spray, a gel-based spray, a behavioral intervention, or usual care. Over six months, the saline spray group experienced a 20% reduction in total illness days compared to usual care, with sustained benefit over 12 months (mean 18 vs. 22 days). The instructions were to use two sprays per nostril at the first sign of an infection or after potential exposure to infection, up to 6 times per day. So people weren’t using the sprays routinely every day – they only started using them when they felt symptoms beginning or after they thought they’d been exposed to someone who was sick. This makes the results particularly interesting, since the sprays were only used reactively when illness was starting, yet still reduced total sick days by about 20% over the 6-month study period.
In a randomized controlled trial published in Scientific Reports, hypertonic saline nasal irrigation and gargling reduced common cold household transmission by 35% and decreased viral shedding.
Systematic reviews and expert consensus statements corroborate these findings, noting that daily saline nasal hygiene modestly reduces household transmission. For Covid, a systematic review found that nine out of ten studies on saline-based solutions reported positive effects in reducing nasopharyngeal viral load, with four studies demonstrating a reduction in transmission with saline irrigation.
Let’s say you go to a wedding, or a Slayer concert with a mosh pit, and you want to reduce your risk of getting sick from said joyous event. If you go home and use some nasal saline, flush and gently blow out the lines, will that reduce your risk? I think so. Viral doses absolutely matter. Like my epidemiology and old school blogging friend Dr. Tara C. Smith once wrote:
So while we are constantly inundated by microbes, the number of microbes that enter our bodies is usually too low to get past our defenses. (A tiny enough dose may even serve to remind our immune system of a pathogen’s existence, boosting our antibody response to keep us protected against it.)
When enough pathogens do manage to breach our defenses and start to replicate, we get sick. Often this is just a numbers game. The more invaders you’re fighting off, the more likely you are to feel ill.
Treatment of illness and symptom relief
Nasal saline sprays and rinses are supported by moderate-quality evidence for modest reductions in symptom severity, duration, and healthcare utilization in the treatment of established viral URIs, including Covid and influenza. Not game changers, but game strategy improvers.
That pilot randomized controlled trial mentioned above evaluated hypertonic saline nasal irrigation and gargling in healthy adults within 48 hours of URI onset. The intervention group demonstrated a reduction in illness duration by ~2 days, decreased use of over-the-counter medications, and a 35% reduction in household transmission.A randomized controlled trial recently presented at the European Respiratory Society Congress found that saline nasal drops can reduce the duration of the common cold in children by 2 days compared to usual care. The study, which included 407 children up to 6 years old, showed that those using saline drops experienced cold symptoms for an average of 6 days, compared to 8 days for those receiving usual care. Additionally, the use of saline drops was associated with a lower rate of household transmission, with fewer family members catching colds in households where children used the drops.
A systematic review by the Cochrane Database assessed saline nasal irrigation for acute URIs, including the common cold and sinusitis. The review found that saline irrigation has benefits for relieving symptoms, particularly nasal congestion and obstruction, with one larger pediatric trial showing statistically significant reductions in nasal secretion and obstruction scores. However, the Cochrane folks pointed out that the clinical significance of these reductions was modest, and the overall quality of evidence was low due to small sample sizes and risk of bias.
For Covid, multiple studies and systematic reviews have reported that saline nasal irrigation reduces nasopharyngeal viral loads, hastens viral clearance, and provides significant symptom relief, particularly when initiated early in the course of illness.[1][2][3][4][5] For one example, a case-control study found that daily isotonic saline lavages significantly decreased nasal symptoms (blocked nose, runny nose, sneezing) by an average of 25%, with high patient satisfaction and only rare, mild adverse effects.
Another small study early in the pandemic looked at 80 high risk patients who were started on nasal saline irrigation twice daily for 14 days starting within 24 hours of their positive Covid test. This was not a randomized trial, but an 8-fold reduction in hospitalization rates was observed when compared to the matched control general population. But this study design was only good enough to make this worth further confirmatory research. I’m still waiting.
Nasal saline sprays and rinses are generally very safe for the general population in both outpatient and inpatient settings, with only minor and infrequent risks. The most common adverse effects are local and transient, including nasal burning, irritation, discomfort, and fluid dripping from the nose. If saline starts coming out of your ears you have done something quite wrong. Side effects are more frequently reported with hypertonic saline formulations compared to isotonic saline, and with high-volume irrigations compared to sprays.
A critical theoretical and known risk is infection from contaminated water used to prepare saline solutions. There have been rare but serious cases of fatal primary amebic meningoencephalitis due to Naegleria fowleri bacteria when tap water was used for nasal irrigation. To mitigate this risk, guidelines from the CDC, FDA, and specialty societies recommend using only distilled, sterile, or previously boiled water for preparing saline solutions, and regular cleaning of irrigation devices.
Commercially prepared saline sprays or rinses have a good safety record as far as I could find.
Current evidence does not demonstrate significant or lasting disruption of the nasal microbiome in the general population when using saline sprays or rinses.
These findings are consistent across multiple guidelines and systematic reviews, supporting the excellent safety profile of nasal saline sprays and rinses when used appropriately: [1][2][3][4][5][6][7][8][9][10]
Practical considerations
Based on the evidence reviewed, the following practical guidance:
Concentration: Both isotonic (0.9%, normal saline) and hypertonic (1.5–3%) solutions appear effective. Hypertonic solutions may provide modestly greater symptom relief but can cause temporary burning or discomfort; reducing salinity or adjusting technique often reduces these effects.
Frequency: Benefits appear dose-dependent. Studies showing the strongest effects typically use irrigation two to four times daily, with some Covid protocols using irrigation every 3–4 hours during acute illness.
Technique: Large-volume irrigation (≥60 mL) using squeeze bottles, neti pots, or pressurized devices appears more effective than low-volume sprays for established infections, though nasal sprays may be adequate especially for prevention. Combining nasal irrigation with gargling may optimize coverage of the oropharynx.
The safest way to give this a try might be to pick up a continuous nasal mist spray like this one for $10 at CVS. The spray keeps going as long as the trigger is pressed, and a gentle nose blow after misting it all up in there clears the pipes. NeilMed also makes a bunch of products, and the University of Washington provides this how-to guide. Neti pots are tricky, but many use them. I tried once and didn’t like it.
I don’t do this stuff regularly… but when I do I use my own questionable technique. It involves reverse osmosis water that is first boiled and then cooled, a cheap nasal saline salt packet to dissolve, a 3 cc syringe with no needle, and my head tilted back. Saline in, then back out the same way. I figured a way to keep most of it from going down my throat which is impossible to describe! Sorry.
Timing: Early initiation (within 48 hours of symptom onset) appears important for maximizing benefit. Later initiation (5+ days) reduces efficacy, though some benefit has still been observed.
Limitations of current evidence
Before I start a nasal saline medical influencer side hustle, we should be honest here. Despite encouraging findings, important limitations must be acknowledged. Most studies are small, and many were not designed to detect differences in severe outcomes like hospitalization or mortality. Study heterogeneity, including variations in saline concentration, irrigation volume, frequency, timing, and patient populations, limits direct comparisons. Some studies lack adequate blinding, and placebo-controlled trials are inherently challenging given that even water-based nasal irrigation provides some mechanical benefit.
The Covid literature evolved rapidly during the pandemic, and many studies were conducted during different variant waves with varying baseline severity, vaccination status, and treatment standards. Post-exposure prophylaxis data remain particularly sparse, relying largely on observational evidence and intuition.
And yet this celebrity was caught using nasal saline by the paparazzi. Influential.
Conclusion
Would I use a nasal saline spray or rinse to help treatCovid, flu, and other nasty respiratory illnesses? Absolutely. I would.
What about to help prevent those infections from taking hold in the first place? Like after an event in which somebody with flu/Covid was almost certainly present. Sure. I would. I have.
I think we are leaving a cheap and easy way to help prevent/treat respiratory infections on the table. A missed opportunity to help prevent flu and Covid and RSV and the rest. Another thin layer of protection in the Swiss cheese model of preventing infections, with other slices like masking, ventilation, and vaccination having holes, too. Together they make a block of cheese. I don’t really like Swiss cheese, but I’ll eat it.
In terms of treatment I did nasal saline with my most recent URI and honestly crushed it. N=1. Science settled! Are you not entertained?!
Click HERE to access URL to view the entire website for the above article.
In addition, one could also view a second website that provides another study which provides evidence that 100 minutes of walking per day lessens back pain by clicking on thisLINK; this article also provides the original meta analysis for those that are interested in the science.
