Happy dog, happy heart

image: (c)Dr David R Hamilton

I find myself writing this piece today because it was 5 years ago on this day that my dog, Oscar (main photo), passed away from bone cancer at the age of just over 2. He came into my life two days before I started writing my book about self love / self esteem, ‘I Heart Me’, and he passed away two days before I submitted the final manuscript to my publisher (Hay House). He was in my life for the exact duration I was working on the book. It helped me deal with the loss to believe that he came into my life to help me.

One of the things he inspired me to do was research some of the beneficial effects of animals in our lives. It turns out that dogs are good for the heart.

In a study of 369 patients who’d had a heart attack, for example, the chances of them having another heart attack within a year was 400% less if they had a dog. While we might logically assume that this figure is entirely due to the exercise of taking a dog for a walk, research suggests that exercise is only part of it. A significant contributing factor is the quality of relationship a person has with their dog.

Research published in ‘Science’, found that when dog owners interacted warmly with their dogs for 30 minutes, for example, oxytocin levels increased by 300% in the humans (and by 130% in the dog). Yes, the dog benefits too. Key is that these numbers only apply to people with good human-dog relationships. There is much less change in oxytocin levels when relationships are not close.

What’s the importance of oxytocin? Well, as well as being a reproductive hormone, it has many other roles in the body. In the brain, it aids bonding and trusting behaviour. When we eat food, it helps digestion by improving gastric motility. It helps wound repair by aiding capillary growth and working with growth factors. But it plays a huge role in the cardiovascular system. It is a cardioprotective hormone – it protects the cardiovascular system. It does this in two main ways, first by reducing blood pressure and second by clearing blood vessels of inflammation and oxidative stress (free radicals).

We find the same kind of effect in human relationships too. People with better quality relationships tends to have healthier cardiovascular systems.

I call oxytocin ‘the kindness hormone’ and have done in my books on kindness (Why Kindness is Good for You, The Five Side Effects of Kindness’ and ‘The Little Book of Kindness (my illustrated book)’), because it is associated with feelings that can be brought on by kindness.

Closeness produces oxytocin, hugs produce it, love produces it, friendship produces it, affection, compassion, gentleness too. It is certainly associated with behaviours of the heart. It’s nice that Nature rewards these heart behaviours with a healthier heart. It’s as if Nature is saying, ‘Yes! More of this please’. Just as we train a dog by offering rewards for certain behaviour, perhaps Nature is training us humans by rewarding our good behaviours.

Dogs don’t ask for much. Other than food, they really just ask that you love them. That makes a happy dog. The emotional reward you get is some happiness. The physical reward is a boost to your cardiovascular system. Happy dog, happy heart!

Of course, the same also applies to other animals we bond with, like cats, rabbits, horses. Indeed, a study of rabbits indeed found that those shown more affection had healthier hearts. All animals have an oxytocin system. Oxytocin is so important to us, and animals, that the oxytocin gene is one of the oldest genes we have, at around 500 million years old. That it’s with us after all this time tells us how important it is for health – ours and that of animals.

It’s the love and kindness that we show each other and to animals that matters.

Be kind. Show compassion and affection. Be gentle. With each other and with animals.

Some things in life are really quite simple.

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  1. Hali Chambers on November 12, 2019 at 4:52 pm

    Awww . . . Oscar. <3 The world would be a different place if everyone could have a consistent, daily dose of oxcytocin. It's one of many reasons massage therapy is so beneficial. Dogs are a special breed, tho. They put the LOVE in "unconditional love." My dogs make me a better human. 😉

    • David R. Hamilton PhD on November 13, 2019 at 11:01 am

      They certainly do, Hali. 🙂

  2. Debi Zimmermann on November 12, 2019 at 10:35 pm

    Firstly, thank-you for this insightful article on the health benefits of sharing life with an animal and for sharing the importance of kindness and compassion in general-heaven knows there is precious little of that in the present world. Secondly, my deepest sympathies in the loss of Oscar-the loss of a companion so pure of heart is devastating but double so if lost at such a young age. I fully understand the profound ways we connect with animals which led me to be a veterinarian for over 30 years where I had my oxytocin levels raised regularly! I also now know that our modern diets and lifestyles cause 90-95% of chronic diseases, like cancer in animals and humans (where cancer rates in children are also escalating) and why my current mission to educate pet parents everywhere on navigating this toxic world to prevent this devastation and heartache. Here’s to many happy and old dogs to hug in the future!

    • David R. Hamilton PhD on November 13, 2019 at 11:00 am

      Thanks so much for your kind words, Debi. It’s wonderful that you have done, and are doing, such great work. Yes, I think we all need to learn so much about diet and lifetsyle, and ensure that animals in our care receive the best. 🙂

  3. Georgina MacLaurin on November 13, 2019 at 9:43 am

    Hello David – I remember you talking about Oscar – I really felt for you when he died and it seemed so unfair at such a young age. I was thinking about him and yourself when my own beloved 10 year old Dylan (Cockapoo) died in May from a non-melanotic melanoma on his right upper lip, we spent two months living in a hotel on the Wirral so he could attend Leahurst, Liverpool University Small Animals unit – a treasured time despite the awfulness of his cancer. I do believe we are gifted certain animals and people in our lives for a purpose and I feel privileged to have lived with Dylan whilst going through family traumas.His best mate, Seamus (Patterdale X) aged 13 felt his loss too and is only now bouncing back. We are lucky aren’t we to have such precious relationships? Best wishes – Georgina.

    • David R. Hamilton PhD on November 13, 2019 at 10:59 am

      I am so sorry for your loss, Georgina. I understand what you were going through. We did everything we could to try to save Oscar, and spent many nights sleeping alongside him. Animals really are so special and they leave such lasting prints on our hearts.

  4. Chris Kent on November 18, 2019 at 7:26 pm

    i remember being so sad that you only had the opportunity to share your life with Oscar for such a short while- although I know he made such a huge impact on your life, and yes helped with the work you were doing. How animals can give us so much still astounds me. I am sure I would not be as physically or emotionally healthy if it were not for my dogs, and my horses. Thanks for sharing these memories of the lovely Oscar.

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