Health benefits of a vegetarian diet
At one time, the case for a vegetarian or vegan diet may have appeared problematic but, over time, it has proved to be good for all stages of life (1).  Indeed, over recent years research has shown that vegetarians and vegans are very healthy and may even be healthier than their meat-eating peers.  Vegetarian diets are generally rich in fruits and vegetables, high in fibre and low in saturated fat (2), a diet encouraged by the Department of Health.  In contrast, the general population consumes too much saturated fat, salt and sugar, with intakes of vitamins and minerals below recommended levels (3,4).  Studies have shown that, overall, people who follow a vegetarian diet have a lower risk of a number of chronic diseases including heart disease, hypertension and cancer (5), whereas populations who consume diets high in meat and fat and low in fibre, fruits and vegetables are at risk (6).

Surveys suggest that typical older vegetarians have a more nutrient-dense diet than meat eaters (i.e. more nutrients per portion) (7), benefit from being leaner than omnivores (8) and have good bowel regularity due to a high fibre diet (9).  In short, a plant-based diet offers potential health benefits and can help to slow the aging process. 

Nutritional guidelines
Although energy requirements generally decrease as we get older, the basic dietary guidelines are the same as for younger adults.   Therefore, whatever the age, whether meat-eater or vegetarian, the recommendations for fat, fibre and carbohydrate are the same (10) so it is important that enough food is eaten to cover energy (calorie) requirements.  Some older people have to modify their diets to help control illnesses such as diabetes and heart disease but if the older person is in good health, it is recommended that they follow the general dietary guidelines for the population (11). 

For those wishing to look at nutritional standards in more detail, standards for macro and micronutrients from each meal have been set by the Food Standards Agency (12)

Vitamin and mineral supplements
There is a lack of specific recommendations for older people for many of the micronutrients (vitamins and minerals), although it is known that the ability to digest, absorb, metabolise and excrete nutrients changes with age.  For example, we get most of our vitamin D from the effect of sunlight on our skin but, as we get older, we have a reduced efficiency of its synthesis in the skin.   People aged 65 years and over (vegetarian and non-vegetarian) are at risk of vitamin D deficiency if they rarely venture outside.  Vitamin D is necessary for calcium absorption (important for bones) so if a person is not having regular exposure to sunlight, a daily supplement of 10mcg is recommended (11).  

Vegans and vegetarians who eat limited dairy products should regularly include a source of vitamin B12.  Absorption of vitamin B12 decreases with age , so regular use of reliable B12 sources is important e.g. eggs and milk products, fortified non-dairy milks, yeast extracts and fortified cereals.  The Vegan Society recommends a daily intake of 3mcg from food or a supplement of 10mcg once a day or 2000 mcg once a week.

Fruit and vegetables – ‘5 A DAY’
The Department of Health recommends that a minimum of 5 portions of fruit and vegetables should be eaten each day, because:
* They're packed with vitamins and minerals.
* They help in maintaining a healthy weight.
* They're an excellent source of fibre and antioxidants.
* They help reduce the risk of heart disease, stroke and some cancers.
* They taste delicious and there's so much variety to choose from.  5 A DAY portions should include a variety of brightly coloured fruit and vegetables to get the maximum nutritional benefits. This is because they each contain different combinations of fibre, vitamins, minerals and other nutrients.

References
1. Mangels AR, Mesinna V, Melina V (2003) Position of the American Dietetic Association and Dietitians of Canada: Vegetarian Diets. J Am Diet Assoc 103 748-65
2. Key TJ, Davey GK, Appleby PN (1999) Health benefits of a vegetarian diet.  Proceedings of the Nutritional Society 58 271-275
3. Henderson et al (2002) National Diet and Nutrition Survey: adults aged 19-64 years.  The Stationery Office                                             
4. Finch S (1998) National Diet and Nutrition Survey: older people aged 74 years +. The Stationery Office
5. Thomas B (2001) Vegetarianism and veganism pp 305 in Manual of Dietetic Practice 3rd edition. Blackwell Publishing
6. Brants HA, Lowik MR, Westenbrink S et al (1990) Adequacy of a vegetarian diet in old age.  Journal of the American College of Nutrition 9 292-392
7. Dwyer JT (1991) Nutritional consequences of vegetarianism.  Annual Review of Nutrition1161-91
8. Thomas B Bishop J (2007) Vegetarianism and veganism pp 383 in Manual of Dietetic Practice 4th edition. Blackwell Publishing
9. Bingham SA (2000) Diet and colorectal cancer prevention. Biochem Soc Trans Feb 28(2)2-6
10. Department of Health 1991
11. British Nutrition Foundation 2004
12. Food Standards Agency - Nutrient and Food Based Guidelines for UK institutions (2006)
13. British Nutrition Foundation 2004