Online you will come across a great many eating plans; many of them promise marked weight loss in a short time. This article does not recommend any of them; it simply explains what needs to be known before moving to such a plan.
In brief
There is no single eating plan that holds for everyone. The World Health Organization (opens in a new tab) says so directly:
“The exact make-up of a diversified, balanced and healthy diet will vary depending on individual characteristics such as age, gender, lifestyle and degree of physical activity, cultural context, locally available foods and dietary customs.”
That sentence explains why any text claiming a plan that suits everyone should be read with caution.
Before moving to a restrictive plan
A restrictive eating plan is a change that can affect not only how much is eaten but also the course of your blood sugar and blood pressure, the effect of the medicines you take, and your general well-being. The following are therefore reviewed beforehand:
- All medicines and supplements taken, particularly blood sugar, blood pressure and blood-thinning medicines
- Co-existing conditions such as diabetes, cardiovascular disease, kidney and liver disease and thyroid dysfunction
- The history of your weight, including which plans have been tried before and how they ended
- Any history relating to eating behaviour
- Whether you are pregnant or breastfeeding
You can read how this assessment is carried out in When Weight Will Not Come Off: What Is Assessed?
The World Health Organization’s general framework
The World Health Organization sets out the following framework for adults:
- Energy balance means “energy intake balanced with energy expenditure”, with an adequate balance between the three sources of energy, protein, fat and carbohydrate.
- At least 400 grams of vegetables and fruit a day are recommended for everyone over the age of 10.
- Free sugars should stay below 10% of total daily energy intake.
- Total fat should be 30% or less of total daily energy intake in adults.
- Salt should be less than 5 grams a day in adults.
This is a general framework, not a personal plan. A plan for you is built as part of Nutrition and Dietary Counselling.
In which patients is this assessed differently?
- In patients taking blood sugar medicines or insulin (doses may need reviewing when the eating routine changes; do not change your dose on your own initiative)
- In patients taking blood pressure medicines (doses may also need reviewing)
- In patients with kidney or liver disease (the dietary adjustment is planned separately)
- In patients who are pregnant or breastfeeding (weight management is taken up in a framework specific to this period)
- In patients under 18 and in older patients (assessment and follow-up are carried out differently)
- In patients with a history relating to eating behaviour (an assessment is made before any restrictive plan is set up)
- In patients taking medicines for weight management (the eating and activity routine is an inseparable part of follow-up; you can read the detail in What Happens When GLP-1 Receptor Agonists Are Stopped?)
How is the process carried out?
- Assessment before the plan. History taking, measurements, blood pressure; laboratory tests where needed.
- Building the plan around the person. As the World Health Organization states, the make-up varies from person to person.
- Reviewing medicine doses. This may be needed when weight and the eating routine change; the decision rests with the physician.
- Follow-up. Weight, waist circumference and blood pressure, and where needed blood sugar and blood lipids, are assessed at set intervals.
- Reviewing the plan. If something new appears, such as weakness, dizziness, hair loss or irregular periods, the plan is taken up again.
Points to be aware of, and the limits
Treat plans that cut out a food group entirely with caution. The World Health Organization’s framework is built on a balance between the three sources of energy.
Programmes based on liquids alone, or that replace meals with products, are not followed without assessment by a physician.
Do not use weight-loss products obtained over the internet. You can read their risks in Why Are Weight-Loss Medicines Obtained Outside the Legal Supply Chain Risky?
Do not change your medicine doses on your own initiative.
Weight coming back is not a failure. The World Health Organization defines obesity as a chronic, relapsing picture; it is a situation that needs assessing.
When should you see a physician without delay?
If you notice these symptoms, consult a physician without delay:
- Signs of low blood sugar such as sweating, trembling, palpitations or sudden hunger
- Dizziness, blurred vision or a feeling of faintness
- Marked weakness and reduced muscle strength
- An irregular feeling in the heartbeat
- Nausea, vomiting or signs of fluid loss that do not settle
- Marked hair loss
- A marked change in your periods
- An unexpected change in your blood pressure or blood sugar readings
In the event of a change in consciousness, fainting, chest pain or shortness of breath, go directly to the emergency department.
Frequently asked questions
Is there a limit to how fast weight should come off?
No threshold figure is given on this page. A suitable rate is set according to the person, any co-existing conditions and the medicines taken, and it is reviewed during follow-up.
Is an eating plan the same for everyone?
No. The World Health Organization states that the exact make-up of a balanced, healthy diet varies with age, gender, lifestyle, degree of physical activity, cultural context and locally available foods.
Is it appropriate to cut out a food group entirely?
The World Health Organization’s framework is built on an adequate balance between the three sources of energy, protein, fat and carbohydrate. Plans that cut out a group entirely are not followed without assessment by a physician.
Is there a general framework for sugar, fat and salt?
For adults the World Health Organization states the following: free sugars below 10% of total daily energy intake; total fat 30% or less; salt less than 5 grams a day. These are a general framework, not a personal plan.
I take diabetes or blood pressure medicines; what should I do when changing my eating routine?
Talk to your physician before making the change. When the eating routine changes, medicine doses may need reviewing; do not change your dose on your own initiative.
What is monitored during a restrictive plan?
Weight, waist circumference and blood pressure, and where needed blood sugar and blood lipids, are assessed at set intervals. If something new appears, such as weakness, dizziness, hair loss or irregular periods, the plan is taken up again.
Can I use the weight-loss products I bought online?
No. Those products fall outside the assurance of the Ministry of Health; you can read their risks in Why Are Weight-Loss Medicines Obtained Outside the Legal Supply Chain Risky? Tell your physician about every product you are thinking of using.
Sources
- World Health Organization, Healthy diet fact sheet, 26 January 2026. https://www.who.int/news-room/fact-sheets/detail/healthy-diet (opens in a new tab)
- World Health Organization, Obesity and overweight fact sheet, 8 December 2025. https://www.who.int/news-room/fact-sheets/detail/obesity-and-overweight (opens in a new tab)
