Common myths and your own plan
Test six popular nutrition claims against the evidence, learn how to judge a new one, and pick three small changes to start with.
Myth 1: "Carbs make you fat"
The claim
Bread, rice and potatoes are what put weight on, so cutting carbs is the key to a healthy weight.
The evidence
Weight goes up when you take in more energy than you use over time, from any source: carbs, fat, protein or alcohol. Whole grains and legumes are carbohydrate foods, and every mainstream guideline recommends them (lessons 1 and 3).
Check yourself
Over months, what mainly causes a person to gain weight?
- Eating carbohydrates of any kind
- Taking in more energy than they use, from any source
- Eating anything after 8 pm
- Not doing a detox regularly
Show the answer
Taking in more energy than they use, from any source
Right. Energy balance over weeks and months is what counts, whichever nutrient the extra energy comes from. The clock and detoxes aren't the cause.
Four more myths, quickly
- "Eating after 8 pm makes you gain weight." The total over the day and week matters far more than the clock. Late eating matters only if it means extra snacking or worse sleep.
- "Honey or brown sugar is healthy sugar." Both are free sugars and count towards the same limit (lesson 9).
- "Fat-free or light means healthy." The fat is often replaced with sugar or starch; check the table (lesson 7).
- "Supplements make up for a poor diet; more vitamins are better." Food comes first, and too much of some vitamins, such as A and D, is harmful (lesson 5). Likewise, gluten-free is only needed for coeliac disease or a diagnosed sensitivity.
Check yourself
Myth, or backed by mainstream evidence?
- Date syrup is a healthy sugar you can have in any amount
- Replacing some saturated fat with olive or canola oil is good for the heart
- A daily high-dose multivitamin makes up for skipping vegetables
- Whole grains and legumes belong in a healthy diet
- "Light" crisps are automatically a healthy snack
- Most adults should eat less salt than they do now
Show the answer
Myth: Date syrup is a healthy sugar you can have in any amount, A daily high-dose multivitamin makes up for skipping vegetables, "Light" crisps are automatically a healthy snack
Backed by evidence: Replacing some saturated fat with olive or canola oil is good for the heart, Whole grains and legumes belong in a healthy diet, Most adults should eat less salt than they do now
Check yourself
A three-day juice cleanse is needed to flush toxins out of your body.
Show the answer
False
False. Your liver and kidneys remove waste continuously. There's no good evidence that cleanses or detox teas help, and a juice cleanse is mostly free sugar with little protein or fibre.
Four questions for any new claim
- Who's saying it, and are they selling something?
A product, a programme or clicks. A sale doesn't make it false, but it's a reason to check.
- Does it promise fast or dramatic results?
"Lose 5 kg in a week", "melt belly fat". Real changes in health are gradual.
- Is it one study, or what the big bodies agree on?
A single small study makes headlines. The WHO and national guidelines weigh all the studies together.
- Does it ban whole food groups?
"Never eat bread" or "no fruit". Mainstream guidance almost never cuts out a whole group for healthy people.
Check yourself
- A national health service page: "Eat more vegetables, whole grains and legumes, and cut down on sugary drinks. Small changes, kept up, make a difference over months."
- A post selling a tea: "Melt 5 kg of fat in 7 days. Doctors don't want you to know this. Cut out all bread and rice while you drink it."
Why should the second claim make you suspicious?
- It's written more confidently
- It's selling something, promises fast results and bans whole food groups
- It mentions doctors
- Tea is always unhealthy
Show the answer
It's selling something, promises fast results and bans whole food groups
Exactly. Three red flags in two sentences: a product for sale, a dramatic promise and banned food groups. The first reads like mainstream guidance: gradual, and nothing to buy.
YOUR PLAN
Three small, specific changes
Big rules ("no sugar ever", "eat perfectly from Monday") tend to be dropped within weeks. Small habits that are specific and easy to repeat are the ones that stick, and they add up. Pick three, write them down, and try them for two weeks before adding anything else.
"Add a vegetable to lunch." "Water instead of soft drinks on weekdays." "One lentil or bean dinner a week." "Taste before salting." "One sugar cube in tea instead of two."
Check yourself
Which of these is a small, specific change most likely to stick?
- "Eat healthier"
- "Add a vegetable to lunch"
- "Never eat sugar again"
- "Change my whole diet tomorrow"
Show the answer
"Add a vegetable to lunch"
Yes. It's clear what to do, you can tell whether you did it, and it's easy to repeat. That's what makes a habit last.
My plan, starting Saturday
1. Add salad or herbs to lunch, every workday
2. Water instead of soft drinks, Saturday to Wednesday
3. One lentil or bean dinner a week
Check in: in two weeks
Keep what worked; swap what didn't.Three habits, written down, with a date to check.Write your own three the same way: what exactly, and when. After two weeks, keep what stuck and add one more, or swap one that didn't fit your life.
Lesson recap
- Weight changes with energy balance over time, from any source; carbs alone and the clock aren't the cause.
- Your liver and kidneys detox you; detox teas and cleanses have no good evidence.
- Honey is still free sugar, "light" doesn't mean healthy, and supplements don't replace food.
- Red flags for a claim: selling something, fast results, one study, banned food groups.
- Pick three small, specific changes, write them down and try them for two weeks; get personal advice when your situation needs it.