---
title: "What happens if — your body"
description: "21 what-if questions in the your body category, each labelled by how confident the answer actually is."
url: https://atoneplace.net/what-happens-if/body/
site: "At One Place"
---

# Your body

21 questions in the your body category.

| Question | Answer | Confidence |
| --- | --- | --- |
| What happens if you stop eating sugar? | Blood glucose steadies within days and dental risk drops immediately; most other changes come from eating fewer calories overall. | Established science |
| What happens if you stop drinking alcohol? | Sleep and liver markers improve within weeks, and blood pressure typically falls — but heavy drinkers must not stop abruptly without medical advice. | Established science |
| What happens if you stop smoking? | Carbon monoxide clears within a day, lung function improves within months, and heart disease risk halves within a year. | Established science |
| What happens if you stop eating meat? | Fibre intake usually rises and saturated fat falls — but vitamin B12 has to come from somewhere, and it is not plants. | Established science |
| What happens if you crack your knuckles every day? | Nothing much. It does not cause arthritis — a doctor tested it by cracking one hand only for 60 years. | Established science |
| What happens if you swallow gum? | It passes through in a day or two. The seven-years story is entirely false. | Established science |
| What happens if you stop drinking coffee? | A withdrawal headache for two to nine days, then nothing — caffeine tolerance resets in about a week or two. | Established science |
| Do you really need eight glasses of water a day? | No. Total fluid needs are met by all drinks and food, and thirst is a reliable guide for most people. | Established science |
| What happens if you only drink water? | Mostly it removes liquid calories — the average person drinking only water cuts several hundred calories a day without noticing. | Established science |
| What happens if you stop exercising? | Aerobic fitness starts falling within about two weeks; strength holds up considerably longer. | Established science |
| What happens if you hold your breath for too long? | You cannot hold it until you die — the reflex takes over, and consciousness ends any voluntary effort long before that. | Established science |
| What happens if you never brush your teeth? | Plaque hardens into tartar within days, gums inflame within weeks, and teeth are lost over years. | Established science |
| What happens if you only eat one food? | You develop whatever deficiency that food lacks — and every single food lacks something. | Established science |
| What happens if you stop eating salt? | Blood pressure usually falls, which is the point — but sodium is essential, and zero is not the target. | Established science |
| Does shaving make hair grow back thicker? | No. Shaving cuts the shaft at its widest point, which makes regrowth feel coarser without changing anything. | Established science |
| What happens if you hold in a sneeze? | Usually nothing — but pinching the nose and closing the mouth redirects real pressure, and rare injuries are documented. | Established science |
| Do you have to wait 30 minutes after eating before swimming? | No. There is no evidence behind the waiting rule — digestion does not divert enough blood to cause drowning. | Established science |
| Does reading in dim light damage your eyes? | No. It causes eye strain and headaches, and does not cause lasting damage. | Established science |
| Can you catch a cold from going outside with wet hair? | No. Colds are caused by viruses; being cold and wet does not create one. | Established science |
| What happens if you never wash your hair? | Sebum, dead skin and dust accumulate; it becomes greasy then matted, and the scalp is likelier to become itchy and flaky. | Established science |
| What happens if you never sleep on your side? | Back sleeping worsens snoring and sleep apnoea for many people; front sleeping strains the neck. Side sleeping is the default for good reasons. | Reasoned extrapolation |

- [What happens if you stop eating sugar?](https://atoneplace.net/what-happens-if/stop-eating-sugar/) — Blood glucose steadies within days and dental risk drops immediately; most other changes come from eating fewer calories overall.
- [What happens if you stop drinking alcohol?](https://atoneplace.net/what-happens-if/stop-drinking-alcohol/) — Sleep and liver markers improve within weeks, and blood pressure typically falls — but heavy drinkers must not stop abruptly without medical advice.
- [What happens if you stop smoking?](https://atoneplace.net/what-happens-if/stop-smoking/) — Carbon monoxide clears within a day, lung function improves within months, and heart disease risk halves within a year.
- [What happens if you stop eating meat?](https://atoneplace.net/what-happens-if/stop-eating-meat/) — Fibre intake usually rises and saturated fat falls — but vitamin B12 has to come from somewhere, and it is not plants.
- [What happens if you crack your knuckles every day?](https://atoneplace.net/what-happens-if/crack-your-knuckles/) — Nothing much. It does not cause arthritis — a doctor tested it by cracking one hand only for 60 years.
- [What happens if you swallow gum?](https://atoneplace.net/what-happens-if/swallow-gum/) — It passes through in a day or two. The seven-years story is entirely false.
- [What happens if you stop drinking coffee?](https://atoneplace.net/what-happens-if/stop-drinking-coffee/) — A withdrawal headache for two to nine days, then nothing — caffeine tolerance resets in about a week or two.
- [Do you really need eight glasses of water a day?](https://atoneplace.net/what-happens-if/drink-eight-glasses-of-water/) — No. Total fluid needs are met by all drinks and food, and thirst is a reliable guide for most people.
- [What happens if you only drink water?](https://atoneplace.net/what-happens-if/drink-only-water/) — Mostly it removes liquid calories — the average person drinking only water cuts several hundred calories a day without noticing.
- [What happens if you stop exercising?](https://atoneplace.net/what-happens-if/stop-exercising/) — Aerobic fitness starts falling within about two weeks; strength holds up considerably longer.
- [What happens if you hold your breath for too long?](https://atoneplace.net/what-happens-if/hold-your-breath/) — You cannot hold it until you die — the reflex takes over, and consciousness ends any voluntary effort long before that.
- [What happens if you never brush your teeth?](https://atoneplace.net/what-happens-if/never-brush-your-teeth/) — Plaque hardens into tartar within days, gums inflame within weeks, and teeth are lost over years.
- [What happens if you only eat one food?](https://atoneplace.net/what-happens-if/eat-only-one-food/) — You develop whatever deficiency that food lacks — and every single food lacks something.
- [What happens if you stop eating salt?](https://atoneplace.net/what-happens-if/stop-eating-salt/) — Blood pressure usually falls, which is the point — but sodium is essential, and zero is not the target.
- [Does shaving make hair grow back thicker?](https://atoneplace.net/what-happens-if/shave-your-hair/) — No. Shaving cuts the shaft at its widest point, which makes regrowth feel coarser without changing anything.
- [What happens if you hold in a sneeze?](https://atoneplace.net/what-happens-if/hold-in-a-sneeze/) — Usually nothing — but pinching the nose and closing the mouth redirects real pressure, and rare injuries are documented.
- [Do you have to wait 30 minutes after eating before swimming?](https://atoneplace.net/what-happens-if/swim-after-eating/) — No. There is no evidence behind the waiting rule — digestion does not divert enough blood to cause drowning.
- [Does reading in dim light damage your eyes?](https://atoneplace.net/what-happens-if/read-in-dim-light/) — No. It causes eye strain and headaches, and does not cause lasting damage.
- [Can you catch a cold from going outside with wet hair?](https://atoneplace.net/what-happens-if/go-outside-with-wet-hair/) — No. Colds are caused by viruses; being cold and wet does not create one.
- [What happens if you never wash your hair?](https://atoneplace.net/what-happens-if/never-wash-your-hair/) — Sebum, dead skin and dust accumulate; it becomes greasy then matted, and the scalp is likelier to become itchy and flaky.
- [What happens if you never sleep on your side?](https://atoneplace.net/what-happens-if/never-sleep-on-your-side/) — Back sleeping worsens snoring and sleep apnoea for many people; front sleeping strains the neck. Side sleeping is the default for good reasons.