Why eating avocados and potatoes can help cut blood pressure - especially if you’re menopausal

Menopausal women concerned about their blood pressure might want to consider increasing their intake of avocados and other potassium-rich foods.

Why? Because they are more sensitive to the damaging effects of salt than others, and new science suggests that increasing your intake of potassium-rich foods (think not just avocados but also salmon and bananas) may help mitigate the impact of salt — and might be more beneficial than cutting back on salt alone when it comes to lowering blood pressure.

Salt pushes up blood pressure as it makes your body retain too much fluid, and possibly affects your gut bacteria, too.

An animal study (not confirmed in humans) found that a high-salt diet can lower levels of ‘good’ bacteria such as Lactobacillus, which in turn reduces the production of short-chain fatty acids, molecules that help keep inflammation in check, it was reported in the journal Hypertension Research in June.

Without enough of these anti-inflammatory molecules, blood vessel walls may become damaged, leading to raised blood pressure.

The benefits of cutting back on salt are beyond doubt. A review of several previous studies, published in the BMJ in 2020, found for every half a teaspoon of salt you cut from your diet, your systolic blood pressure reading (the first number, and the one most associated with heart attack and stroke risk) could drop by 1.1 mmHg and the diastolic reading (bottom number) could drop by 0.3mmHg.

To see a drop in systolic blood pressure of around 5 mmHg, you would need to cut about one-and-a-half teaspoons of salt from your daily intake.

Despite such findings, we remain a nation of salt lovers.

According to the 2018/2019 UK National Diet and Nutrition Survey, the average Brit eats more than 8g salt a day — about 40 per cent higher than the recommended limit of 6g (just over a teaspoon) — 70 per cent of which is hidden in ultra-processed foods such as bread, breakfast cereals and ready meals rather than added at the table.

While reducing ultra-processed foods is a great way to cut down on salt, what might improve your blood pressure and potentially your general health even more is improving the balance between the salt, or specifically sodium (table salt is around 40 per cent sodium), and potassium in your diet.

This gained interest in science circles after a study published in January 2024 in the journal BMC Public Health found that the ratio between these two nutrients has a bigger impact on blood pressure than focusing on either one alone. In fact, the study of 2050 participants — which took account of their intake of salt (sodium) and potassium — found those with the highest intake of potassium had a 56 per cent reduced risk of cardiovascular disease (which can result from unchecked high blood pressure).

It’s thought that potassium helps counteract salt’s effect by relaxing your blood vessels, flushing out extra salt through your urine, and keeping your body’s fluid balance in check, which helps lower blood pressure.

But it’s the balance between sodium and potassium that matters most for heart health.

The finding may be especially beneficial to post-menopausal women, who become more sensitive to salt as, after menopause, lower oestrogen levels make it harder for the body to regulate sodium, leading to more noticeable blood pressure spikes.

But it is also relevant to many of us, as an estimated 4.2 million people don’t know they have high blood pressure, according to the Office for National Statistics. So here are my tips to improve your sodium-to-potassium balance.

USE POTASSIUM SEASONING

Regular table salt is roughly 40 per cent sodium, and the rest is chloride, trace minerals and anti-caking agents to stop it clumping.

Potassium salt, also called low-sodium salt, replaces some sodium chloride with potassium chloride. Switching to one of these low-sodium salts can make a big difference to your heart health.

A 2021 study in the New England Journal of Medicine, involving more than 20,000 people across nearly five years, found that using a salt substitute lowered systolic blood pressure by 3.3 mmHg and their diastolic reading by 0.7 mmHg.

The study also found no significant increase in the risk of hyperkalaemia (too much potassium), even for those with high blood pressure, making it a safe option for most people (unless you have kidney issues).

Low-sodium salts still have some sodium, so they count toward your 6g daily limit. But with much less than regular salt, they make a smaller impact overall.

HAVE A BAKED POTATO FOR LUNCH

If you are a salt lover, I would suggest you try and include sources of potassium in your daily diet.

Many people believe bananas to be the best source, but while one banana contains about 450 mg of potassium there are other everyday foods that contain more than twice as much — including one cup of Swiss chard or beet greens, or even a humble baked potato.

In fact, leafy greens such as kale, beans such as chickpeas, dairy products and certain fish —such as salmon and sardines — all contain high levels.

We should all be getting plenty of potassium in our diet. A 2024 study published in the journal BMC Public Health found that eating at least 3500 mg of potassium each day is linked to a lower risk of death from all causes.

To reach that amount you would need to eat a banana, an orange, a sweet potato, a baked potato, a cup of spinach and a cup of kidney beans in a day — which is doable for most of us.

RETHINK THAT HAM SANDWICH

White bread accounts for the lion’s share of the UK population’s salt intake, according to the latest National Diet and Nutrition Survey (followed by bacon and ham).

That’s not surprising when you consider that about 75 per cent of sliced breads have as much salt per slice as a packet of ready salted crisps.

You do need to add salt to make bread; it adds flavour and also helps with fermentation.

But there’s a range in salt levels across different brands, with some containing as little as half a gram per 100g, while others contain up to three times that — and on average about 0.4g per slice.

White bread tops the list as it is the most popular bread in the UK. However, a 2023 report by Action on Salt found wraps and wholegrain bread can still pack in significant amounts of salt.

So check the labels, or the traffic light system (which highlights various nutritional content) on the front of shop-bought breads.

If you’re a fan of a ham sandwich, choose a low-salt bread and consider swapping the ham for lower-sodium sliced chicken or turkey. And add veggies such as lettuce, tomatoes and cucumber to add potassium.

ADD MUSHROOMS TO BOOST FLAVOUR

Let’s not forget the main reason we add salt to food — it makes it tastier.

But the good news is that in just two weeks, we can retrain our taste buds to enjoy food with less salt. Research shows that using spices and herbs can help lower the amount of salt needed without sacrificing flavour.

Try roasting vegetables in mixed spices (roasting naturally intensifies flavours, too) or mixing fresh herbs into dishes.

Umami-rich ingredients such as mushrooms and tomatoes also boost flavour (and provide potassium), while using fresh citrus juices or vinegar can give a tangy kick.

PS: HAVE THAT SALTY SNACK IN THE MORNING

If you’re planning to eat salty foods, it might be better to enjoy them earlier in the day.

A 2021 review in the American Journal of Hypertension suggests that our bodies may be better at getting rid of sodium earlier in the day when we’re more active.

This means eating salty foods in the morning could have less of an effect on your blood pressure than if you eat them in the afternoon or evening. This is because blood pressure tends to rise during the day and dip at night when you’re resting.

The researchers speculated that eating salt earlier allows the body more time to flush out the excess sodium, potentially preventing higher blood pressure at night.

While much of this research comes from animal studies, it may apply to humans, too.