How many vegetables a day is enough?

Enough is at least 400 g of vegetables and fruit a day, which works out to 5 portions of 80 g in total. The UK's NHS explains that its 5 A Day advice is based on the World Health Organization's recommendation of a minimum of 400 g a day, and that it means 5 portions in total, not 5 of each. One portion is about 3 heaped tablespoons of cooked vegetables, or 1 banana. Thai national surveys find that most people eat less than this.

What is the daily amount of vegetables and fruit to aim for?

400 g, or 5 portions of 80 g

The NHS sets the adult portion at 80 g, so 5 portions add up to 400 g. Vegetables and fruit are counted together. Two portions of fruit and three of vegetables reach the line, and so do four portions of vegetables and one of fruit.

What Thailand's own guidelines say

Thailand's food-based dietary guidelines, promoted since 1996, include "eat plenty of vegetables and fruits regularly" as one of nine guidelines. A 2011 paper by Sirichakwal and colleagues at Mahidol University's Institute of Nutrition describes how, in 1998, the quantitative part of these guidelines was set out as a picture guide, the Nutrition Flag (ธงโภชนาการ). The 2019 and 2021 national surveys analysed by Phulkerd and colleagues converted the servings people reported into grams using standard servings adapted from the Nutrition Flag, and counted 400 g a day as enough.

How much is one portion of vegetables or fruit?

Grams are hard to judge at a food stall, so it helps to know what 80 g looks like. These examples come from the NHS portion guide:

For children, the NHS gives a rough guide: 1 portion is the amount they can fit in the palm of their hand.

What counts, and what does not

The NHS rules on what counts towards 5 A Day:

• Fresh, frozen and canned all count, 80 g each. Vegetables in cooked dishes and ready-made foods count too. For canned food, choose ones in water or natural juice with no added sugar or salt.
• Juice and smoothies count as 1 portion at most: 150 ml, with the combined total limited to 150 ml a day.
• Beans and pulses count only once a day, however many you eat.
• Potatoes, yams, cassava and plantain do not count, because they are usually eaten in place of other sources of starch, such as rice or bread.
• Sweet potatoes do count, because they are usually eaten in addition to the starchy part of the meal.

How many vegetables do Thai people actually eat?

Several national surveys have asked Thai people how much vegetables and fruit they eat. Most people fall short of 400 g.

Each survey used its own serving sizes and methods, which are not necessarily the same as the NHS's 80 g portion, so read the figures as an overall picture rather than comparing them directly.

The third national health survey

The NHES III analysis by Satheannoppakao and colleagues at Mahidol University, published in 2009, found that intake was lower among men (except for vegetables), older people, people with less education or lower household income, and people living in rural areas. The survey used a short food frequency questionnaire, and the data are now some years old.

Older adults

A national survey analysed by Phulkerd and colleagues at Mahidol University's Institute for Population and Social Research found that 31.9% of people aged 60 and over ate at least 400 g a day. People who lived alone were the least likely to eat enough. Servings were estimated from pictures of one serving of raw and cooked vegetables and fruit.

A repeat survey in 2019 and 2021

A nationally representative longitudinal survey in 2019 and 2021 found that only 19.7% of 3,115 participants ate at least 400 g a day in both years. Another paper from the team notes that only about 1 in 3 Thais reached 400 g a day in 2018. All of these figures are self-reported.

For more national figures on salt, sugar and other foods, see What do Thai people eat, according to national surveys?

How can I reach 400 g with Thai meals?

Use the 2:1:1 plate

The 2:1:1 healthy plate, recommended by the Thai Health Promotion Foundation (ThaiHealth) and explained in Ramathibodi Hospital's @Rama magazine, divides a 9-inch plate into 4 equal parts. Two parts, half the plate, are vegetables: any fresh or cooked vegetables, eaten in variety. One part is rice or other starch, and one part is meat, fish or eggs. The hospital also suggests fruit as a snack 1 to 2 times a day, a small plate each time, choosing less sweet fruit such as apple, guava or dragon fruit.

An example day

Here is one way about 5 portions can fit into a working day. The portion counts are rough estimates against the NHS sizes (3 heaped tablespoons of cooked vegetables, or 1 medium fruit, per portion); the amount of vegetables in a dish varies a lot between shops and menus.

One-dish meals such as chicken rice or a holy basil stir-fry with egg often come with only a few pieces of vegetable. Adding a vegetable side dish or a bag of cut fruit fills the gap. If you live alone and often eat one-dish meals, see Living alone with patchy meals: how can I cover food groups?

Variety matters as well as amount

The Nutrition Source at Harvard T.H. Chan School of Public Health says the more vegetables and the greater the variety, the better, and suggests trying to include, on most days, dark green leafy vegetables, yellow or orange vegetables and fruit, red vegetables and fruit, beans and peas, and citrus fruit. Thai markets offer all of these: morning glory, Chinese kale, pumpkin, carrots, tomatoes, long beans and pomelo, for example.

How should I wash and prepare vegetables?

If you worry about chemical residues on vegetables, it may help to know what others do. A national study of non-farmers by Phulkerd and colleagues found that 9% of those living in urban areas grew vegetables or fruit at home, and that people who feared pesticide contamination were more likely to garden. You do not need to grow your own to eat enough. The US FDA gives 7 simple steps for cleaning fresh produce:

1. Wash your hands for 20 seconds with soap and water before and after preparing fresh produce.
2. Cut away damaged or bruised areas.
3. Rinse produce before you peel it.
4. Gently rub produce under plain running water. There is no need to use soap or a produce wash.
5. Scrub firm produce, such as melons and cucumbers, with a clean vegetable brush.
6. Dry produce with a clean cloth or paper towel.
7. Remove the outermost leaves of a head of lettuce or cabbage.

Who should check before changing what they eat?

The 400 g line is general advice for the public. If a doctor has told you to limit certain foods, follow their advice. If you are unsure how much is right for you or your child, ask a doctor or dietitian at a hospital or health centre.