Dr Roderick Mulgan MB, ChB, MPP, LLB (Hons) is a community doctor who specialises in aged-care in Auckland. He has long held an interest in the impact of lifestyle choices, particularly diet, on long-term health. When the pandemic arrived, he turned his attention to the lifestyle choices that underpin immunity.
In Build Your Immunity for Life he sets out the science that shows many of us do not consume the micronutrients our immune system needs. He also traverses the immune implications of body weight, fasting and sleep. Although the worst of this pandemic is behind us adequate immunity is a topic for the ages. Roderick talks to NZ Booklovers.
Tell us a little about Build Your Immunity for Life.
It is a discussion of some fairly deep science, rendered I hope explicable. It ties together two big concepts: one is that even well fed people often lack essential micronutrients like zinc and vitamin A, for various reasons, like exhausted topsoil, and our low sunlight position on the planet (vitamin D). The other is that these key micronutrients are vital to well functioning immunity. Even with vaccines and antibiotics we need robust personal immune systems as interventions only work as well as the bodies they are put into. Unfortunately, personal tests for most of what we are talking about don’t exist (I discuss that phenomenon in its own chapter). It is therefore useful to know what dietary items to particularly target. Offal meat, for instance. It is usually the least valued product of a food animal but nutritionally the richest. Liver is where the animal stores its own micronutrients, and the best way for the next animal in the food chain (us!) to acquire them. I also identify the particular usefulness of dietary fat, whole grains, shell fish, and eggs from hens that get sunlight.
In parallel, there are lifestyle considerations that are vital for our best immunity: the right body weight, the right sleep, fasting sometimes, and giving the bacteria in our large bowels what they need to be happy.
What inspired you to write this book?
I wrote The Internal Flame, which was an account of how deep seated slow burn inflammation causes big diseases like cancer and heart attacks, which did reasonably well. When the pandemic happened I thought personal immunity would be another topic the public would be interested in. Unfortunately, chewing through several hundred papers on diet and lifestyle can’t be done in 6 months, so when the book was ready the pandemic was largely behind us, but I hope people retain an ongoing appreciation of how important it is.
What research was involved?
Basically perusing major databases of scientific journals and going through a pile of them for each topic.
What was your routine or process when writing this book?
I spilt my time between my law and medical practices, half the week each. Law has gaps in it and I would dive into the book manuscript whenever I got a chance. I envy authors who can give their main working hours to the project.
What did you enjoy the most about writing Build Your Immunity for Life?
Discovering new things. I personally never knew that there are such widespread dietary deficiencies in well fed parts of the planet, that our immune system goes through 24 hour cycles and that is why it needs sleep, that bacteria that invade us need iron from our tissues and this is why we often don’t absorb it when we eat it, that New Zealand is vitamin D deficient because we get so little sun, and multiple other useful insights into human health.
What are a few things you hope readers will take from away from the book?
That there is more, a lot more, to personal immunity and overall health than eating meat and three veg and getting in some exercise occasionally. That was good advice 30 year ago; now health aware people must consider specific food items like offal meat (and alternatives for vegans), how to feed their bowel bugs, the utility of fasting, the right body weight, how to safely get sunlight, and multiple other specific interventions.
What is the favourite book you have read so far this year and why?
Eating to Extinction by Dan Saladino. We think conservation is about the Hectors Dolphin and the coral of the Great Barrier Reef, which of course it is. But in this beautifully written book the author lays out in detail the way corporate uniformity is killing foods and food making processes. All sorts of diverse grains and fruits now exist in tiny numbers or food banks. Red rice, blue bananas; we may lose them and their genes forever. Likewise rare breeds of animals. Also, methods. There is a traditional way of making beer in Belgium which uses open vats that get seeded by the natural microflora of centuries old oak beamed brewhouses. It is rapidly losing ground to the bulk producers who make a uniform product in stainless steel. We need to know and think about these things.
What’s next on the agenda for you?
I continue to write on health topic via a column in Life and Leisure magazine. That will do to be going on with.