What heart and kidney specialists taught me about apples, coffee and your mouthwash

Lifestyle is Medicine

On Friday, I was lucky enough to attend the Cardiorenal Forum in London, an educational day where cardiologists and nephrologists (heart and kidney specialists) come together to share the latest clinical updates.

The heart and kidneys are deeply connected. When one struggles, the other often follows, which is why it is so valuable when these two specialities sit in the same room. It was a fascinating day. Science and medicine are truly incredible, and I left with my head full of new research.

But what struck me most among all the talk of new medications and complex trials, some of the most powerful findings were about the simple, everyday things we do. What we eat, what we drink and how we look after ourselves. Here are my four biggest takeaways.

1. An apple a day? Make it two

A randomised trial found that adults with mildly raised cholesterol who ate two apples a day for eight weeks saw their LDL cholesterol (often called the "bad" cholesterol) fall, compared with drinking an apple juice-style drink with the same sugar and calories. The reduction was modest, a few per cent, but it came from a whole food that is cheap, easy to find and travels well in a handbag. Researchers think the fibre (particularly pectin) and natural plant compounds called polyphenols are doing the work, which is why whole fruit beats juice.

Try this: keep a bowl of apples where you can see them, and eat them with the skin on, where many of those polyphenols live.

2. Your mouthwash may be working a little too hard

Our mouths are home to friendly bacteria that help turn nitrates from foods like leafy greens and beetroot into nitric oxide. Nitric oxide helps our blood vessels relax, which supports healthy blood pressure. Strong antiseptic mouthwashes can wipe out these helpful bacteria along with the unhelpful ones, and studies have shown this can blunt nitric oxide production and nudge blood pressure upwards. There is also growing interest in how the mouth's bacteria influence the gut, although that research is still emerging.

Try this: if you use mouthwash out of habit rather than on advice, consider whether you really need it daily. Brushing twice a day, cleaning between your teeth, and regular dental check-ups remain the foundations. If your dentist has prescribed a mouthwash for a specific reason, please keep using it and talk to them before making any changes.

3. Good news for coffee lovers

For years, people with atrial fibrillation (AF, an irregular heart rhythm) were often told to cut out caffeine. A recent trial called DECAF turned that thinking on its head. People with AF who had undergone a procedure to reset their heart rhythm were asked either to drink at least one cup of caffeinated coffee a day or to avoid caffeine completely. Over six months, the coffee drinkers had a significantly lower chance of their AF coming back. Large population studies point in a similar direction, linking moderate coffee intake with a lower risk of heart rhythm problems.

Try this: if you enjoy a morning coffee, you may not need to feel guilty about it. Keep it moderate, notice how your body responds, and if your own cardiology team has given you personal advice about caffeine, follow that.

4. Omega-3 and the kidneys: a striking result

The PISCES trial looked at people receiving haemodialysis, a group at very high risk of heart attacks, strokes and other cardiovascular problems. Those who took a daily fish oil supplement containing the omega-3 fats EPA and DHA had 43% fewer serious cardiovascular events than those given a placebo.

That is a remarkable result for a population where very few treatments have been shown to make this kind of difference. It is important to say, though, that this was a high, carefully measured dose in a specific group of patients under medical supervision. High-dose omega-3 is not right for everyone, and some studies have linked it with a higher risk of AF in other groups.

Try this: for most of us, the simplest way to get omega-3 is through food. Aim for two portions of fish a week, one of them oily, such as salmon, mackerel, sardines or herring. If you are on dialysis or have a heart or kidney condition, please speak to your own team before starting any supplement.

If you are vegan or vegetarian: plant foods provide a different omega-3 called ALA. Good sources include ground flaxseed (linseed), chia seeds, hemp seeds, walnuts, rapeseed oil, soya and tofu. Sprinkling a spoonful of ground flaxseed or chia over porridge, or snacking on a handful of walnuts, is an easy daily habit.

The catch is that our bodies convert only a small amount of ALA into EPA and DHA, the forms studied in trials like PISCES. Fish do not make EPA and DHA themselves; they get them from algae. That means an algae oil supplement can provide EPA and DHA directly, without any fish involved. As with any supplement, it is worth checking with your GP, pharmacist or specialist team first, particularly if you take blood thinners or have a heart or kidney condition.

The bigger picture

At the forum we heard that heart failure is expected to double by 2040, driven by rising rates of high blood pressure, obesity and type 2 diabetes. As a heart failure nurse, that figure stays with me. But here is the hopeful part. High blood pressure, excess weight and type 2 diabetes are all strongly influenced by how we live. Medicine is extraordinary and has its place, but what we eat, how we move, how we sleep and how we care for ourselves every day has the greatest impact on our long-term health.

Two apples, a mindful morning coffee, a second look at the mouthwash and a couple of portions of fish a week. Small, achievable changes that add up.

If you would like support understanding your own heart health risk factors and building habits that genuinely fit your life, I would love to help. You can find out more at Island Holistic Healthcare.

‍This article is for general information and does not replace individualised clinical advice. If sleep disruption is significantly affecting your quality of life, please speak with your GP or a qualified healthcare practitioner.