Guides

One guide per subject, built on the research we publish in full.

All of it is free: the research, the guides, the downloads. Knowledge is not what we sell.

A man set up to pull a loaded barbell off the floor in a gym. His hips are down, his back is flat and his hands are on the bar, with morning light falling across the matting.

Strength

What lifting does to the risk of dying, how little of it is actually required, and why grip strength predicts more than almost anything else you can measure at home.

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A plate of salmon, broccoli, salad leaves, quinoa, avocado and tomato on a wooden table by a window. Beside it are a glass of water, a bowl of berries, a bottle of olive oil and half an avocado, and at the edge a dumbbell and a smartwatch.

Metabolic health

The five numbers that describe it, what fitness turned out to be worth against them, and the two-minute intervention with a randomised trial behind it.

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Somebody rests both hands on their belly. On the wooden table in front of them stand jars of sauerkraut, kimchi, pickles and beetroot, two bowls holding yoghurt and cabbage, and fresh garlic and ginger.

Gut

What a randomised trial found when it fed people fermented food for ten weeks, why the fibre in your food beats the bacteria in a capsule, and what to do if your gut is actually unhappy.

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A man at a wooden table with his face in his hands. In front of him a laptop, a mug and a stack of paper, and on the wall behind him the sun draws the shadow of a houseplant.

Stress

What a stress response is, what happens when it stops switching off, what the research measured it doing to a heart, and what actually lowers it.

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A man sits cross-legged on a mat by a tall window, eyes closed and chin slightly raised. One hand rests on his chest and the other on his belly, with trees in full leaf outside.

Breathwork

The one part of your nervous system you can operate on purpose, what five minutes a day was actually measured to do, and the four patterns worth knowing.

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Light

Bright days and dark nights, what the largest study of personal light exposure found, and the honest verdict on blue-light glasses, including the part that does not favour us.

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A corner of a room with a large window looking onto dense woodland. Ferns and a palm stand in earthenware pots, a jute rug lies on the floor, and afternoon light falls across the wall in stripes.

Air, noise and green

Air, noise and green space: the three exposures that act on you every day whether you think about them or not, and what the largest studies found.

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An artery in cross section, seen from the inside. Yellow plaque lies along both walls, and red blood cells push through the narrowing left between them.

Your lipid panel has five or six numbers on it and they are not equally important. Which one carries the risk, which one is a message about something else, and how far diet and training actually move them.

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A glucose molecule as a ball-and-stick model: black carbon atoms in a ring, with red oxygen and white hydrogen around them, floating above a blue cell surface.

Blood work: blood sugar

Fasting glucose, HbA1c and insulin measure three different things and they disagree more often than anyone tells you. What each one sees, what it misses, and which of them a trial has ever moved.

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Fibre

The one nutrient almost nobody reaches, what the evidence for it actually says, and how many grams are really in the food you already eat.

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A wooden table in morning light holding about ten small bowls of capsules and powders: white capsules, beige ones, green, black, two kinds of powder, and a bowl of amber fish oil softgels. Behind them a glass of water, a preserving jar and a brown apothecary bottle, with a plant at the edge of the frame.

Supplements

What the large randomised trials found when they tested the four supplements everybody takes, which one survived, and how to read a label without being sold to.

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