“A diet designed just for you”: your genes, your gut bacteria, your blood type, your personality. It’s one of the wellness industry’s most seductive pitches, and it reaches parents constantly, often aimed at post-baby weight or a fussy child’s “sensitivities.” This page once ran a version of it. Here’s where personalised and fad diets stand: what has real evidence, what’s clever marketing, and what works for a busy family.
The more a diet is personalised to sound scientific, the more suspicious you should be, because the evidenced advice is boringly the same for almost everyone.
Blood-type diets, most DNA-based “eat for your genes” plans, and detoxes have little or no solid evidence behind them. The dull truth the industry sells against is that the fundamentals work for nearly everybody, cost nothing to know, and can’t be packaged as a proprietary secret: mostly whole foods, plenty of vegetables, not too much sugar and ultra-processed food, roughly the right amount.
Reading the personalised-diet pitch
- DNA / “nutrigenomics” diets. The science is real but early. Genes influence some nutritional responses. The consumer products racing ahead of that science, promising a bespoke meal plan from a cheek swab, are largely overselling; independent reviews have been underwhelmed. Interesting field, not yet a reliable purchase.
- Blood-type diets. Popular, and not supported by evidence. Studies find any benefit comes from the healthier eating the plans happen to encourage, not the blood-type matching.
- Gut-microbiome tests and plans. An exciting research area, and not yet ready to tell you what to have for lunch. Treat direct-to-consumer versions with caution.
- Detoxes and cleanses. Your liver and kidneys already do this, for free, continuously. There’s nothing a juice cleanse detoxifies.
- Elimination diets for children. The one to be most careful with: cutting food groups from a child’s diet based on a “sensitivity test” or a wellness trend, instead of a diagnosed allergy or a doctor’s advice, risks real nutritional harm. Suspected allergies go to a doctor, not an app.
What works for a family
None of it is proprietary and all of it is dull, so it doesn’t get advertised at you:
- Mostly whole foods, lots of vegetables and fruit, not much ultra-processed stuff. That single sentence outperforms almost every branded plan.
- The family eats the same way. Cooking one healthy way for everyone beats special plans per person, teaches children by example, and is the only version a busy household sustains.
- Sustainable beats optimal. The best diet is the one you’ll still be doing in a year, which rules out most fads by design, since they’re built to be intense and brief.
- For a real concern like a child’s growth, a genuine intolerance or post-natal recovery, see a doctor or a registered dietitian. That’s the personalised advice, and it’s grounded in your situation, not a swab and a sales funnel.
Frequently asked questions
Do personalised or DNA-based diets work?
The underlying science is real but early; the consumer products promising a bespoke plan from a swab are largely ahead of the evidence, and independent reviews are unconvinced. For now, treat them as interesting, not reliable. The fundamentals of good eating are the same for nearly everyone.
Are detox diets and cleanses good after having a baby?
No. Your body detoxifies itself continuously, and there’s nothing a cleanse adds. Post-baby, sustainable whole-food eating and patience serve recovery far better than any cleanse, and anything more specific is a conversation for your doctor.
Should I put my child on an elimination diet?
Only on medical advice. Cutting food groups from a child’s diet based on a trend or a “sensitivity test”, and not a diagnosed allergy, risks genuine nutritional harm. Suspected allergies go to a doctor, who can test properly.
What diet is best for a family?
Mostly whole foods, plenty of vegetables, limited ultra-processed food and sugar, everyone eating the same way, and a pattern you can sustain for years. It’s unglamorous and unbranded. That’s precisely why it works and doesn’t get advertised.
The main points
The more scientific and bespoke a diet sounds, the more skeptical to be. Blood-type, most DNA plans, and detoxes don’t hold up. What works is dull and universal: whole foods, lots of vegetables, the whole family eating the same sustainable way. And take any real concern, a child’s diet, an intolerance, recovery, to a doctor or dietitian, the only personalisation worth paying for.
Read next
- Food and allergy prevention: the advice has reversed
- The toddler snack formula
- Exercising through pregnancy: the full guide