N° 59 | September 2011

Eat plenty of vegetables and fruits everyday

Today, eating more vegetables and fruits for better health is a concept with which most of the general public is familiar. However, only in recent times, with new research findings, have we really begun to understand the mechanisms of action of vegetables and fruits in health promotion and disease prevention.

Which vegetables and fruits should we choose?

Vegetables and fruits most commonly cited as offering a protective effect are onions, garlic, red pepper, carrots, spinach, cabbage, broccoli, brussels sprouts, cauliflower, tomatoes, and raw, fresh citrus fruit1,3. While the evidence seems to consistently point to specific vegetables and fruits, studies on individual nutrient action on disease prevention are still inconclusive. There are probably many other active substances in vegetables and fruits which are as yet unknown, and the interactive and synergistic effect of nutrients in foods cannot be discounted. Encouraging a variety of vegetable and fruit intake is therefore still the best overall advice.

Are south africans eating sufficient vegetables and fruits?

What is optimal intake? — The professional’s opinion
An intake of at least five portions (400 g) of vegetables and fruits per day has become established as a manageable, minimum recommendation by numerous international and national health promotion agencies, producers and retailers4-9.

How much is ‘plenty’? — The consumer’s view
Findings from the South African Food-Based Dietary Guidelines Consumer Study10 highlighted that consumers interpreted the word ‘plenty’ in two ways:
(1) frequency (‘as often as possible’; ‘every day’) and (2) quantity (‘at least two per day’). Numerical values ascribed to the word ‘plenty’ ranged from a minimum of one vegetable and one fruit a day to as many as five to nine vegetables and/or fruits a day.

How many vegetables and fruits are South Africans eating?
Regional and ad hoc food and nutrient studies describe a similar trend between cultural groups and rural/urban dwellers, namely, and average two main meals a day with small quantities of vegetables and fruits, with women consuming notably more vegetables and fruits than men11- 14. Overall intakes of vegetables and fruits for South Africans can therefore be regarded as not meeting the global recommendations of five portions daily.

What are the barriers to eating vegetables and fruits?

Although aware of the health benefits of eating plenty of vegetables and fruits every day, participants of the South African Food-Based Dietary Guidelines Consumer Study10 indicated a number of constraints, in particular, affordability (lack of household income), availability (and therefore highly contingent on seasonal fluctuations), and household taste préférences (with children and sometimes men being most resistant to vegetable and fruit consumption in the household).

Similar barriers to the consumption of vegetables and fruits have been reported among low income, multi-ethnic worksite groups in the United States, who cited perishability, inconvenience, cost, storage difficulties, preparation time, taste dislikes, poor availability, and difficulty changing old habits15,16; and in the United Kingdom, who cited cost, complacency and family influences17,18.

Strategies to overcome barriers to achieving optimal intake

Knowing why and what to eat does not Always translate into a change in food selection — people eat food, not nutrients. The greater challenge is being able to advise people in simple and practical ways while overcoming barriers to change.

For any educational messages to have a positive impact on behaviour, they should be adapted and customised to meet the needs and resources of the individual(s) for whom the messages are intended. Where food insecurity exists or financial constraints prevent frequent consumption of vegetables or fruits, suggestions for increasing consumption may need to focus more on promoting self-sufficiency, e.g. establishing vegetable gardens.

Apart from having a consistent educational message, multiple marketing strategies should be used to enhance the effectiveness with which the message reaches the consumer. Retailers can merchandise the message in their supermarkets, run newspaper advertisements that provide consumers with supplementary information, give away educational materials, and create interactive events to promote awareness. A comprehensive national media campaign can provide systematic and focused coverage of events. At a community level, the message can be brought to consumers through the cooperative efforts of health, educational, agricultural and voluntary agencies working with groups in the private sector. Schools, worksites, clinics, farmers’ markets and food assistance programmes can be used to promote the message and community intervention studies conducted to determine the effectiveness of the message19.

Conclusion

There is adequate evidence to support a dietary guideline for increased vegetable and fruit consumption in South Africa. Increased vegetable and fruit consumption also assists in meeting other dietary guidelines, such as increased intakes of starchy foods and decreased intakes of fats. This dietary guideline should therefore not be seen in isolation, but as one aspect of healthy eating that fits in with the other food-based dietary guidelines. While health professionals may be in agreement as to the necessity of such a dietary guideline, the challenge lies in showing the consumer how this can be realistically achieved given their specific constraints. Health professionals can do much to accelerate this process by providing individual, regional, provincial and national strategies to overcome barriers to change.

  1. Tavani et al. Am J Clin Nutr 1995; 61: suppl, 1372S-1377S.
  2. Block G. Am J Clin Nutr 1991; 53: 270S-282S.
  3. Steinmetz K et al. JADA 1996; 96: 1027-1039.
  4. USDA (United States Department of Agriculture). Nutrition Today 1997; 32(4): 172-173.
  5. NTF (Nutrition Task Force). Wellington, New Zealand: Department of Health, 1991.
  6. Health and Welfare Canada. Canada: Ministry of Supply and Services, 1992.
  7. Hunt P et al. Journal of Human Nutrition and Dietetics 1995; 8: 335-351.
  8. Commonwealth of Australia. Publication No. 2425. Australia: Commonwealth Department of Health and Family Services, 1998.
  9. Malaysian Ministry of Health. Malaysian Dietary Guidelines. Kuala Lumpur: National Coordinating Committee on Food and Nutrition, 1999.
  10. Love P et al. S Afr J Clin Nutr 2001; 14(1): 9-19.
  11. Vorster H et al. Durban: Health Systems Trust, 1997.
  12. Walker A. Nutr Res Rev 1996; 9: 33-65. 28. Mackeown J et al. Ecology of Food and Nutrition 1994; 33: 27-36.
  13. UNISA (University of South Africa). Research Report No. 205. Pretoria: UNISA Bureau of Market Research, 1994.
  14. Bourne L et al. Cent Afr J Med 1994; 40: 140-148.
  15. Cohen N et al. Am J Nutr Ed 1998; 30: 381-386.
  16. Cox D et al. Nutrition and Food Science 1996; Sept/Oct (5): 44-47.
  17. Kilcast D et al. Nutrition and Food Science 1996; Sept/Oct (5): 48-51.
  18. Dittus K et al. Am J Nutr Educ 1995; 27: 120-126.
  19. Heimendinger J et al. Am J Clin Nutr 1995; 61: suppl, 1397S-1401S.
Return