Personalised Nutrition: Why the Same Eating Plan Doesn’t Suit Everyone

An eating plan can look excellent on paper and still be a poor fit for the person trying to follow it.

It might assume you have time to cook every evening, enjoy foods you dislike or tolerate large portions of legumes. It might provide too little food for your activity level, or be unnecessarily complicated for your budget.

Personalised nutrition means adapting advice to relevant differences between people. That includes nutritional needs and health conditions, but also appetite, culture, food access, preferences and everyday routines.

Useful personalisation can begin with an honest look at your meals. A commercial test is not a prerequisite.

Shared foundations, flexible choices

People have different needs, but that does not mean nutritional guidance has no common ground.

The Australian Dietary Guidelines provide a foundation of varied foods from the five food groups. Recommended amounts differ with age and life stage, while activity and body size can affect how much food a person needs.

Personalisation translates those foundations into a workable pattern.

One person might enjoy porridge and yoghurt for breakfast. Another might prefer eggs on toast. Someone else may need a portable breakfast for an early shift.

The meals do not need to look identical to contribute to a nutritious day.

What is worth personalising?

Factor	What it may change in practice
Age and life stage	Nutritional priorities, suitable portions and practical ways to eat enough
Activity and appetite	Meal size, snacks and how much food is needed across the day
Diagnosed health conditions	Specific food choices or restrictions, guided by appropriate clinical advice
Digestive tolerance	Portions, fibre sources and preparation methods
Culture and preferences	Ingredients, flavours and familiar meals that make the plan enjoyable
Budget, access and routine	Shopping choices, convenience foods, batch cooking and meal timing

Some changes require clinical assessment. Others are ordinary planning decisions, such as choosing frozen vegetables or making lunches ahead.

A plan should account for both.

Does personalised advice help?

The Food4Me randomised trial compared conventional advice with several levels of personalised advice in adults from seven European countries.

After six months, personalised advice produced greater improvements in some dietary behaviours and a modest improvement in an overall diet-quality score. Adding body measurements and blood-marker information, or adding those measures plus five genetic variants, did not further improve the effectiveness of the advice in that trial.

The findings concern dietary behaviour over six months, not proof of longer life or prevention of disease. They do, however, show that tailoring advice to someone’s existing diet can be useful without requiring increasingly complex testing.

Start with the problem you actually want to solve

“Eat better” is a reasonable intention, but it can be difficult to act on.

A more useful starting point might be:

•   “I regularly miss lunch because work gets busy.”

•   “My breakfast rarely contains a protein food.”

•   “I want more fibre, but large bean servings make me uncomfortable.”

•   “I need dinners that fit our household budget.”

•   “My appetite has changed and meals are becoming difficult.” These lead to different solutions.

Someone who misses lunch may need a reliable meal they can assemble in five minutes. Someone struggling with digestive symptoms may need assessment and more careful changes, rather than a longer list of foods to avoid.

Choose one priority that would make a meaningful difference to your day.

Adapt familiar meals before replacing your whole diet

Personalisation often works through adjustments to meals you already enjoy.

Change the portion

Two people can share the same dinner and need different amounts. One might want more rice or an additional snack; another might prefer a smaller meal.

Change the ingredient

Swap a disliked vegetable for one you enjoy, or choose a suitable protein food that fits your preferences and budget.

If a medical condition requires a substitution, make sure the replacement meets that need and contributes useful nutrition.

Change the format

A meal may work better packed as a rice bowl, prepared as soup or assembled from convenient supermarket ingredients.

The format should fit the person eating it, including their cooking facilities and schedule.

Change the preparation routine

Cook an extra portion for another meal, keep a few dependable ingredients available or plan two easy dinners for the busiest nights.

Australian healthy-eating guidance includes meal planning, using seasonal or discounted foods, substituting ingredients and making use of leftovers as practical budget strategies.

Personalise for digestive comfort without unnecessary restriction

Digestive symptoms can make generic advice difficult to follow.

Someone told to eat more fibre may need to consider the type, amount and pace of increase. In IBS, a dietitian-guided low-FODMAP approach may sometimes be appropriate, followed by structured reintroduction and a personalised longer-term diet. It is not intended to become permanent avoidance of every FODMAP-containing food.

Useful information includes what you ate, the approximate portion, symptoms and your bowel pattern. A brief record can support a consultation; it does not diagnose a food intolerance.

Do not keep excluding more foods because one meal felt uncomfortable. Persistent symptoms need assessment, particularly if eating is becoming restricted or stressful.

For the wider digestive picture, read our healthy digestion guide.

What can commercial nutrition tests tell you?

Different tests answer different questions. A personalised-looking report is only useful if its findings support a reliable decision.

DNA-based diet tests

Genetic information can identify particular variants. That is different from proving that a commercial food list based on those variants will improve your health.

NHMRC advises consumers to consider the accuracy and usefulness of direct-to-consumer genetic testing, and cautions against using it as the sole basis for clinical decisions.

The Food4Me results also illustrate that adding selected genetic information does not necessarily improve dietary advice. This does not dismiss legitimate medical genetic testing; it highlights the need to assess the particular use being proposed.

Our precision nutrition and DNA guide explores this in more detail.

Gut microbiome tests

A commercial microbiome report may describe microbes detected in a stool sample. Turning that information into a validated diagnosis or a precise dietary prescription is a separate challenge.

A 2025 international consensus statement highlighted limited evidence for the clinical usefulness of microbiome testing and concerns about inappropriate direct-to-consumer applications.

It is therefore important to ask whether the test has demonstrated value for the decision you are considering. This discussion concerns microbiome profiling; it should not be confused with clinically indicated stool tests for specific medical questions.

Read Food-Microbe Pairings and Personalised Nutrition for more on the underlying science.

Food IgG “sensitivity” panels

Commercial food IgG panels should not be used to diagnose food allergy or intolerance.

ASCIA states that there is no credible evidence supporting their use for those purposes. Food IgG antibodies can be present in healthy people and can reflect exposure to a food rather than a disease caused by eating it.

Removing foods on this basis can create unnecessary restrictions. Suspected allergy needs appropriate medical assessment, not a home reintroduction experiment.

Questions to ask before buying a test or programme

Before spending money, ask:

1.  What specific question will this answer?

2.  Is there evidence that using this test improves a meaningful outcome?

3.  Who will interpret the result and explain its limits?

4.  What would change compared with an assessment of my diet and health history?

5.  Does the provider also sell the supplements or products it recommends?

6.  What are the full costs and how will my data be used?

A test may be appropriate when it addresses a relevant clinical question. More measurements alone do not establish a better eating plan.

A practical example: adapting a soup meal

A flexible soup can make personalisation manageable within a household.

If you use Broth & Co bone broth as your savoury base, adjust the other ingredients and serving size to suit the people eating it.

What needs adapting?	A practical option
A larger appetite or more active day	Include an adequate portion of the soup, with additional rice, potato or bread if wanted
A preference for a heartier meal	Include chicken, beans, lentils or another suitable protein food
A cautious increase in legumes	Begin with a smaller amount within a familiar meal and adjust according to tolerance
A busy schedule	Choose a recipe that can be prepared ahead and stored safely for another meal
Different household preferences	Serve herbs, lemon, grains or other additions separately

This is meal planning, not a prescribed treatment.

The recipe still needs to suit any diagnosed allergies or medical dietary requirements. Broth does not make every ingredient combination suitable for everyone.

Our bone broth comparison guide and vegetable-forward soup recipes offer starting points.

Review what the change achieves

Useful questions include:

•   Can I manage this on an ordinary working day?

•   Do I enjoy the food?

•   Is the plan affordable?

•   Am I eating enough and maintaining reasonable variety?

•   Are symptoms improving, staying the same or worsening?

•   If a clinician identified a health concern, what follow-up did they recommend?

Do not judge a plan solely by body weight, a single “gut score” or whether you followed it perfectly.

Seek a GP or Accredited Practising Dietitian’s help if symptoms persist, appetite changes significantly, weight changes unexpectedly or food restriction is making adequate eating difficult. Professional support can also help adapt meals around diagnosed conditions.

Frequently asked questions

Do I need a DNA or microbiome test to start?

No. Useful changes can begin with your current diet, health needs, preferences and circumstances. Testing should have a clear purpose and evidence relevant to the decision it is meant to inform.

Can a family share meals while eating differently?

Yes. A common meal can be adapted through portions, side dishes and additions. Diagnosed allergies and medical dietary needs may require more specific planning.

Does finding a suitable plan mean eating the same foods forever?

No. Your preferences, routine, appetite and health needs can change. Review the pattern when circumstances change, and seek advice if new symptoms or medical needs arise.

Choose one practical change that addresses a real difficulty. Build from what you can enjoy, afford and maintain.

You might also like

•   Food-Microbe Pairings and Personalised Nutrition

•   Precision Nutrition Explained: Can Your DNA Really Tell You What to Eat?

•   The Complete Guide to Healthy Digestion

•   Protein-and-Fibre Recipe Collection

References

1.  Australian Government, Eat for Health. How much do we need each day?.

2.  Celis-Morales C and colleagues. The Food4Me European randomised controlled trial. InternationalJournal of Epidemiology, 2017.

3.  Australian Government, Eat for Health. Healthy eating on a budget.

4.  Monash University. The three steps of the FODMAP diet.

5.  NHMRC. Understanding direct-to-consumer genetic DNA testing.

6.  Porcari S and colleagues. International consensus statement on microbiome testing in clinicalpractice. The Lancet Gastroenterology & Hepatology, 2025.

7.  ASCIA. Evidence-based versus non-evidence-based allergy tests and treatments.

8.  Healthdirect Australia. Dietitians.