5 ways to control your blood sugar, reverse insulin resistance, and reduce your heart disease risk | Prof Rob Semple

1 in 4 people have insulin resistance, which quietly raises your risk of heart disease and cancer, often without any change in your blood sugar.

And most of those who have it have no idea. It can remain completely hidden for years, with no obvious symptoms and no warning signs… But it can be reversed.

Today, Professor Rob Semple, a world-leading expert on insulin resistance, explains what insulin does in your body, why you need it to live, and what happens when it stops working properly.

By the end of this episode, you will understand how to spot the warning signs and have practical steps you can take to protect yourself.

If your last blood test came back "normal," how confident are you that it tells the whole story? Are you overlooking one of the biggest drivers of chronic disease?

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Timecodes

00:00 Intro

00:46 Why insulin might be the most important hormone in your body

01:53 What happens if your body stops making insulin

05:20 Why not having insulin used to be a death sentence

11:19 What happens to your brain when blood sugar drops too low

14:01 Why "just lower your insulin" advice can backfire

17:12 The shaky, sweaty feeling an hour after eating, explained

18:42 The exact moment insulin resistance turns into diabetes

21:47 Why high insulin can affect your ovaries

24:15 A visible skin sign that insulin levels are too high

25:40 The organs most at risk when blood sugar spirals

27:17 How common insulin resistance really is in the US and UK

30:23 Why your ovaries can be an early sign of insulin resistance

32:49 Debunking the online "signs" of insulin resistance

35:37 Is insulin resistance actually reversible?

36:47 Why your weight matters more than your BMI number

38:53 The DEXA scan that revealed hidden visceral fat

41:14 Why white bread might not be so different from a can of Coke

43:56 Why one type of exercise burns blood sugar best

45:17 Do you really need two hours in the gym to see results?

46:38 How stress directly changes your blood sugar

48:32 Why irregular sleep might be hurting your blood sugar

49:38 The one piece of advice for anyone worried about insulin resistance

55:00 Why insulin resistance may have once been a survival advantage

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Mentioned in today's episode

Insulin resistance is a risk factor for 12 types of cancer, Nature (2026)

Association of insulin resistance with cancer, American Journal of Cancer Research (2016) 

Global prevalence of insulin resistance, Frontiers in Endocrinology (2025)

Risk Reclassification Beyond BMI, (JACC) (2026)

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Episode transcripts are available here.