4 ways your thoughts affect your metabolism, gut and longevity | Sarah Ann Macklin

Rupy Aujla (0:00)

I'm Dr. Rupy, and on this show, I help you feel more in control of your health through food and lifestyle medicine.

What if I told you that two people could eat the exact same meal with the exact same calories and have completely different hormonal responses because of what they believed about what they were eating? Or that a group of women lost weight and dropped their blood pressure by 10% just by changing the way they thought about their daily activity? Well, these aren't fringe findings. The way we think about our health can meaningfully impact our biology. My guest today is nutritionist Sarah Ann Macklin, Sunday Times' bestselling author of Healthy Shouldn't Be This Hard. On this episode, we're going to unpack four ways in which our thoughts can either help or hinder our health. There's a body of evidence showing that the belief you hold about your food, your movement and even your genes can rewire your biology. And while we all need to learn the art of self-compassion to truly shape our health for the better.

Sarah Ann Macklin, how is it possible that our thoughts can affect our hormones and our health?

Sarah Ann Macklin (1:22)

So my background is a nutritionist, and I was always really aware about how important food is, right? For how we think and how we feel. And it is, there's so much to be said in that. But there is a massive missing ingredient here when it comes to how we look at ourselves with health information, how we relay health information and how we interpret health information. And so for me, yes, it's bi-directional. It's not just the food that affects our mind. It's bi-directional. Our mind can also affect our entire physiology. And that to me was the missing kind of the missing picture. And so I first started coming across this research by an incredible researcher at Stanford called Dr. Elia Crumb. And she is someone who I have looked up to now for years. She did this fascinating study called the milkshake study. So what she did is she gave two participants, I would quite like to be in this actually, if I'm honest with you, two participants, what she told them was milkshakes. And she said to one group, this has around 600 calories in. And she said to the other group, this has got around 180 calories in. She labeled one indulgent and one diet. So just think about how many times you're going out, maybe looking at drinks and ordering something that's diet or healthy or like, oh, I'm going to indulge tonight and have something a bit more delicious.

And then she looked afterwards at the participants and how they responded with their hunger hormone. And the one that was indulgent, their hunger hormone actually decreased, which meant that they felt more fuller and they didn't want to eat anymore. The ones in the diet group, their hunger hormone didn't change.

What was interesting is both of those milkshakes, both contained 380 calories.

Rupy Aujla (2:57)

So they were identical?

Sarah Ann Macklin (2:58)

They were identical.

And so sometimes when you're relaying figures, it can be hard to catch up, but basically neither was indulgent or diet. They were both exactly the same. But the perception that the participants had in that study thought actually changed the way that their hunger hormone related to what they thought and perceived that milkshake to be.

Rupy Aujla (3:19)

This is wild.

Sarah Ann Macklin (3:20)

Isn't it wild? As I'm thinking, hang on, for years, I've been seeing clients in clinic as a nutritionist, and I'm like, this is really healthy. No, this is more indulgent. We shouldn't be having this this often. And if you're thinking about when you read in the news or when you're looking on Instagram, the way the linguistics of how food is described and interpreted has the biggest effect, maybe more than the food itself.

And so I'm like, wait, that should be the baseline of scaffolding when we're talking about health and food. And so that took me down an entire massive journey as a nutritionist to totally change the way that I kind of work with clients, work with myself, but also really wanted to get this message out into the world that actually, before we start with all the external metrics, which can work and do work, sometimes people can be doing all the right things with health. I'm sure you've seen this and I've been there myself. I'm doing all the right things and yet I'm still feeling terrible. I'm still not getting that result. And it's the mindset piece that's so important.

Rupy Aujla (4:25)

It's so important. I'm so glad you wrote the book and you're, you know, the book is littered with a whole bunch of these different examples that are unpacked today. There is another example in your book around this whole idea of how you can adjust your hormones with thoughts with another study from Ellen Langer about sugar labeling and blood glucose in actual people with type 2 diabetes. So those with a metabolic condition can still be primed by the way something is labeled on a drink.