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    Guides and research, with the study attached, including the ones that found nothing.

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  • Guidance

    If you would rather not do it alone: twelve weeks, built on your own numbers.

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Research

Systematic reviews and meta-analyses, read in full and reported with the numbers intact.

What we write about

Is your phone next to your bed ruining your sleep? Not the radiation

· 6 min read · 7 sources

Is your phone next to your bed ruining your sleep? Not the radiation

The radiation has been measured in thousands of people and nothing turns up. The device does turn up, and almost all of it is the half hour you spend holding it in bed.

Read article
How bad are sugary drinks, and how do you drink one least badly?

· 5 min read · 6 sources

How bad are sugary drinks, and how do you drink one least badly?

In trials where adults were given one sugary drink a day on top of their normal diet, they gained 0.83 kg. Taking one a day away gave half a kilo back. And when you do have one, what is already in your stomach decides how big the sugar spike is.

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Is chewing gum bad for you? What your body thinks is coming

· 10 min read · 14 sources

Is chewing gum bad for you? What your body thinks is coming

The worry is that chewing gum makes your body release insulin as if food were coming, which would matter if you are fasting. Chewing does send that signal, with saliva and gut hormones. When researchers measured the insulin, it had not moved.

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Which health tracker is accurate, and is it safe to wear one all day?

· 13 min read · 12 sources

Which health tracker is accurate, and is it safe to wear one all day?

Per measurement, from the validation studies, with what we would pick for each one. Plus the other half nobody asks: what a sensor strapped to your skin around the clock is actually doing to it.

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What does blue light do to your circadian rhythm?

· 7 min read · 10 sources

What does blue light do to your circadian rhythm?

Blue light suppresses melatonin and shifts your body clock. But intensity and timing weigh more than colour, and people differ more than lamps do.

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Do blue light glasses help with tired eyes?

· 9 min read · 13 sources

Do blue light glasses help with tired eyes?

One trial found the relief wearers report. Another swapped the lens for an equally dark grey one, and the benefit disappeared. What is left that works.

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Guides

One guide per subject, built on the research we publish in full. Every claim traced to a source, including the studies that found nothing.

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.

Free

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.

Blood work: lipids

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.

Free

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.

Free

A wooden table covered in high-fibre food: a bowl of broccoli, sprouts, avocado, chickpeas, oats, chia seeds and raspberries, and around it wholemeal bread, kale, an artichoke, berries, walnuts and almonds.

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.

Free

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.

Free

The sun sits low and breaks through the trunks of a pine wood. The grass in the foreground catches the backlight, and a lake and the hills beyond it lie in the distance.

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.

Free

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.

Free

A man photographed from behind in a home gym, in black shorts and white socks, arms at his sides. A squat rack and a kettlebell stand behind him and an olive tree by the window.

One-sided dominance

How one dominant side starts a chain that runs all the way up into your neck, how to work out which link comes first in you, and what to do about it.

Free

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