Can you help your heart with a healthy gut?

Published: 24 June 2019

As we learn more about the wide-ranging health benefits of a healthy gut, we question the links with our heart health.

What are gut bacteria?

Our digestive system is also called our gut and it’s one of the most fascinating organs in the body. The gut is a staggering nine metres long and is home to trillions of different types of bacteria.

The bacteria that live in your gut are collectively called your ‘gut microbiome’. These bacteria not only help you to break down food, they also work all over your body to help you stay healthy.

Most of these bacteria are ‘good’ bacteria which help to keep your levels of ‘bad’ bacteria low.

How is our gut linked to our health?

The food we eat plays a big role in the makeup of our gut microbiome.

Over the past 10 years scientists have revealed how a healthy gut can impact many areas of our health beyond digestion.

Our gut health plays an important role in keeping our immune system strong and researchers have also found links with our mood and mental health (including anxiety and depression)¹.

Scientists have uncovered a link between our gut health, mood and mental health.

Can a healthy gut lead to a healthy heart?

Scientists are learning more about how the substances that our gut microbes produce affect our risk of chronic diseases, like heart disease, diabetes and cancer.

Some research has shown that eating foods that contain probiotics (which are live bacteria found in fermented foods) may help to reduce your total cholesterol and levels of ‘bad cholesterol’ (low-density lipoprotein (LDL)), but the evidence for this is still very limited².

Other research shows a link between the variety of the different types of bacteria in our gut and the health of our blood vessels. This suggests that a healthy diet and probiotics could help to reduce the risk of heart disease³.

One possible link is when you eat animal foods like red meat and eggs, the bacteria in your gut can produce a chemical (called trimethylamine-N-oxide or TMAO). Having this chemical in our blood may be linked to inflammation and the build-up of plaque in our arteries and therefore increase our risk of heart disease. However, the research is mainly from studies in animals and although there are some signs of a connection it is an important area of future research⁴.

What to eat for a healthy gut?

A diet based on plenty of plant foods is not only heart-healthy but it’s gut healthy too.

Types of plant foods include:

• vegetables and fruit with the skins on where possible
• legumes like chickpeas, kidney beans, black beans and lentils
• whole grains like oats, barley, bulgur wheat and quinoa
• nuts and seeds.

Plant foods that are high in dietary fibre help to feed the ‘good’ bacteria in your gut. If you eat a variety of plant foods, in a range of colours, it’ll be better for your gut health.

Examples of high fibre plant foods including vegetables, fruit, whole grains, legumes, nuts and seeds.

The bonus of oats and barley is that they’re not only high in dietary fibre, but they also contain beta-glucan. Beta-glucan acts as food for your ‘good’ gut bacteria and helps to lower cholesterol⁵.

If you don’t eat a lot of high-fibre foods and want to increase your dietary fibre intake, you can gradually eat more whole grains like oats and barley. Just make sure that you drink plenty of water as fibre needs fluid to work.

You can also try to eat fermented foods that naturally contain ‘good’ bacteria. Examples include yoghurt (with live cultures like acidophilous yoghurt), kefir (fermented milk drink), kimchi and sauerkraut (fermented cabbage). Find out more about fermented foods.

Examples of fermented foods including kimchi, vegetables, sauerkraut, yoghurt and cider vinegar.

The bottom line…

Good gut health doesn’t need to be complicated or expensive. You can create a healthy gut microbiome just by eating lots of different plant foods that are close to how they’re found in nature, every day. These are foods like vegetables, fruit, whole grains, legumes, nuts and seeds.

Plant foods are not only healthy for our heart, but they are healthy for our gut too. It makes sense that many heart-healthy eating habits such as eating less red meat, limiting salt and sugar, eating less processed foods and more plant foods will have a positive effect on your gut microbiome too.

There is some new research that shows a healthy gut may have a positive impact on our cholesterol, blood vessels and heart health. However, as the research is still developing we need to wait for more research to understand how our gut health and heart health are linked.

What we do know is that looking after your gut microbiome will help you to lead a healthier life which will impact on your heart health too.

What are the best foods for my heart?

Lily Henderson, NZRD

National Nutrition Advisor

I am passionate about improving the health of all Kiwis from young through to old. I have enjoyed working in nutrition in the UK, Australia and New Zealand.

References:

1. Lassale C et al. Healthy dietary indices and risk of depressive outcomes: a systematic review and meta-analysis of observational studies. Molecular Psychiatry, 2018

2. Cho, Y.A., Effect of Probiotics on Blood Lipid Concentrations: A meta-analysis of randomized controlled trials. Medicine, 2015. 94(43):e1714

3. Menni C, et al. Gut microbial diversity is associated with lower arterial stiffness in women. European Heart Journal, 2018. 39 (25): 2390–2397

4. Wilson Tang, W.H et al. Gut Microbiota in Cardiovascular Health and Disease. Circulation Research, 2017. 120(7): 1183–1196

5. AbuMweis SS et al. Β-Glucan from Barley and Its Lipid-Lowering Capacity: a Meta-analysis of Randomized Controlled Trials. European Journal of Clinical Nutrition. 2010. 64(12):1472-1480.