Inhaltspezifische Aktionen

Veröffentlichungen • Raw Food Eaters: Health Habits and Nutrient Intake

C. Strassner, S. Doerries, K. Kwanbunjan , C. Leitzmann

Poster for the 16th International Congress of Nutrition,
27.7-1.8.1997, Montreal, Canada

Abstract

International recommendations for a healthy diet include a substantial consumption of fresh uncooked fruit and vegetables as a source especially for vitamins, minerals and other protective factors. Much research has been conducted on the effect of a low consumption of these foodstuffs, which is reflected by the average Western diet, but not on a high consumption. In order to examine the latter effect on humans the nutritive status of a group of raw food eaters whose diet consist almost exclusively of fruit and vegetables was examined. Such an alternative dietary regimen are the so-called raw food diets (RFDs) which, though known under this one name, consist of a wide variety of different RFD, most of which are vegetarian regimens. Common to all is the high proportion of raw food in the diet: extreme forms consist of a nutrition comprised solely of raw foods. Health habits were investigated by means of a detailed questionnaire. Data from this nationwide survey indicate that a quarter to a third of the participants are underweight according to their BMI. Extreme RFD are more often practiced by younger participants and by males. Most are highly content with their diet and almost 98% intend to follow their RFD as a long-term regimen. About half the participants gave an own disease as the reason for changing to a RFD. Women who adhere to the stricter forms stated that their menstruation became infrequent or stopped altogether. Food consumption and nutrient intake were calculated from a 7-day-estimated food record. For most participants the consumption of raw food lies above 90%. The diet consists primarily of fruit and vegetables and is augmented by small amounts of nuts, seeds and sprouts. The intake of nutrients that are usually provided by foods of animal origin such as vitamins B12 and D, zinc and calcium is insufficient. On the other hand, the intake of certain protective nutrients, such as Vitamin C and other antioxidants, lie above the national average.

Introduction

International recommendations for a healthy diet include a substantial consumption of fresh uncooked fruit and vegetables as a source especially for vitamins, minerals and other protective factors. Much research has been conducted on the effect of a low consumption of these foodstuffs, which is reflected by the average Western diet, but not on a high consumption. In order to examine the latter effect on humans the nutritive status of a group of raw food eaters whose diet consists almost exclusively of fruit and vegetables was examined. Such alternative dietary regimens are the so-called raw food diets (RFDs) which, though known under this one name, consist of a wide variety of different RFDs, most of which are vegetarian regimens. Common to all is the high proportion of raw food in the diet: extreme forms consist of a nutrition comprised solely of raw foods, some including raw eggs, meat and seafood.

Objectives

  • to determine the nutrition and health habits of people following RFDs in Germany
  • to determine the consumption patterns of foods and beverages of raw food eaters who are omnivore (includes all food groups), vegetarian (exclusion of meat, fish, sea foods and products thereof) or vegan (as for vegetarian plus exclusion of dairy products and eggs)
  • to determine nutrient intakes of people following a RFD and compare these to German recommendations, which differ slightly for some nutrients to international recommendations and RDAs

Methodology

Recruitment took place by call-ups for project participation in 9 different nation-wide magazines and by flyers at appropriate lectures, congresses and self-help organisations. Participants were screened by a short pre-questionnaire. Criteria for study partici-pation and a description of the collective are shown in Fig. 1. Health habits were investigated by means of a detailed question-naire. Primary areas of interest over and above socio-demographic data were food preference and avoidance, health and disease as well as physical activity and relaxation. The questionnaire includ-ed a food frequency table over one month for assessing food intake patterns. A 7-day estimated food record was especially developed and validated for this study. Nutrient intakes were calculated using the German Nutrient Data Bank (Bundeslebensmittelschlüssel Version II.1) and CALORA, a nutrient calculation programme.

Results: 1. General Description

Extreme RFDs are more often practised by younger male participants. Of the collective 64% indicated health as the reason for changing to a RFD, followed by performance reasons (9%) and eco-logical reasons (3%). More than half the participants (61%) gave an own disease as the reason for changing to a RFD. Illnesses most often named in this connection were allergies (n=12), gastro-intestinal diseases (n=9) and rheumatism (n=8). Most of the participants were highly content with their diet and 98% intended to follow their RFD as a long-term regimen. The majority of the collective did not consume alcohol (58%) while most of the remainder (38%) had a consumption under 15g/d. Many of the participants regularly made use of a relaxation technique: for a minimum of 1 hour/week 26% meditated, 21% used self hypnosis and 21% practised yoga. About 47% of the participants stated that they fasted regularly. Of these, 57% followed a total fast while 31% followed a juice fast.

Fig. 1: Participation criteria and collective description

 

Criteria

Description

participants (n):

 

n = 201

gender:

 

female and male

age:

25-64 yrs

median: 46 yrs

duration of diet:

³ 14 months

median: 3,5 yrs

proportion raw food:

³ 70%

median: 97%

 

non-smokers

 

 

Fig. 2: Proportion of food groups (%) in the total diet

 

Fig2

 

2. Body Mass Index (BMI)

Using the internationally accepted classification the data indicate that almost 2/3 of the female participants and more than 2/3 of the male participants are classified with normal body weight (Table 1). More women are underweight than overweight in the collective, whereas more men are overweight than underweight. Studies linking the BMI to the lowest mortality found that the "ideal" BMI increased with age. Using such a classification scheme 57% of the participants fall below the recommended BMI, 42% are classified as ideal and 1% have a BMI above that recommended for their age class. Taking each gender separately (Table 2) shows a more favourable distribution for men: the majority of every age group except 55-64 years attains the recommended BMI. In none of the age groups does a majority attain the ideal BMI for the female participants. In fact, 4/5 of the top age group have a BMI below the recommendation.

Table 1: Classification of participants according to their BMI
compared to the national distribution

 

RFD Study

Germany

Classification

Class women men women men

women

men

 

n

n

%

%

   
underweight

27

10   5,6   3,8 £ 19 £ 20
normal weight

70

66 46,5 43,7 > 19 - £ 24 > 20 - £ 25
overweight

9

18 36,3 41,9 > 24 - £ 30 > 25 - £ 30
Adipositas

1

-    1,61 10,6 > 30 > 30
total

107

94 100 100    

 

Table 2: Classification of participants (%) according to their age and BMI

age

ideal BMI

total participants

female participants

male participants

in years

.

under

ideal

over

under

ideal

over

under

ideal

over

25-34

20-25

50,0

50,0

-

54,5

45,5

-

45,8

54,2

-

35-44

21-26

52,2

47,8

-

63,6

36,4

-

41,7

58,3

-

45-54

22-27

46,3

51,9

1,9

53,1

46,9

-

36,4

59,1

4,5

55-64

23-28

75,9

22,2

1,9

80,6

16,1

3,2

69,6

30,4

-

 

3. Food Consumption Patterns

Fig. 2 shows for the total collective that about 2/3 of the diet consists of fruit. Almost 1/4 consists of vegetables, more than 90% of which are eaten raw. Cereals products, nuts and dairy products each make up slightly more than 1% of the diet while all remaining food groups hardly make an individual contribution. Table 3 gives the average consumption of foods by the collective according to the inclusion of animal products in the diet. Fruits most eaten, irrespective of gender or variant, are apples, oranges and bananas (average 100-300 g/d). Potatoes, bread & baked goods and cereal products play a marginal role compared to the average western diet. The consumption of soya products is less than in other alternative dietary regimens. Where foods of animal origin are consumed, these are preferred raw. A number of differences in the consumption of food groups could be statistically proven, mainly between the vegan variant and each of the other 2 groups.

 

Table 3: Mean food consumption (g/d) of the participants following omnivore, vegetarian and vegan RFDs

Food Groups

p1,2

omnivore
(n = 56)

p1,3

vegetarian
(n = 90)

p1,4

vegan
(n = 55)

. .

mean

90% CI

.

mean

90% CI

.

mean

90% CI

foodstuffs, total

0,0803

2293

1074-4054

0,0035

1948

1100-3431

0,7943

2144

718-4088

raw foods, total

0,2650

2159

991-4054

0,0022

1787

935-3308

0,2488

2098

663-4074

foods of plant origin

0,2637

2190

1016-3956

0,0219

1908

1099-3332

0,5642

2141

718-4088

foods of animal origin

0,0000

109

11-293

0,0000

40

1,0-132

0,0000

0,0

-

fruit & fruit products

0,3232

1559

608-3012

0,0099

1279

451-2712

0,2389

1522

404-3492

vegetables and legumes

0,9929

481

111-995

0,6507

477

172-852

0,7352

519

52-1298

nuts

0,0470

32

0,0-109

0,0863

25

0,0-90

0,3802

29

0,0-134

seeds

0,4205

21

0,0-115

0,2508

15

0,0-49

0,8704

27

0,0-134

bread & baked goods

0,0000

27

0,0-151

0,2296

25

0,0-112

0,0000

2,2

0,0-8,4

cereal products

0,0361

23

0,0-81

0,3007

39

0,0-198

0,0013

18

0,0-160

soya products

0,1517

0,0

-

0,0223

3,1

0,0-29

0,2462

7,7

0,0-7,2

dairy products

0,0000

40

0,0-247

0,0000

38

0,0-151

0,0000

0,0

-

eggs, total

0,0000

7,1

0,0-60

0,7280

3,6

0,0-17

0,0001

0,0

-

meat & meat products

0,0000

38

0,0-187

0,0000

0,0

-

1,0000

0,0

-

seafood

0,0003

36

0,0-199

0,0000

0,0

-

1,0000

0,0

-

1 Test of significance according to Mann-Whitney (U-test) between 2 omnivore and vegan, 3 omnivore and vegetarian,
4 vegetarian and vegan

not significant

p < 0,05

p < 0,01

p < 0,001

 

4. Nutrient Intakes

Table 4 shows the nutrient intakes of omnivore, vegetarian and vegan participants. Omnivore RFDers have a significantly higher nutrient energy intake than vegetarian and vegan RFDers. In both vegetarian and vegan groups the majority of the participants do not achieve the German recommendations for nutrient energy intake when age and gender are considered. For Vitamins A, E, B6, and C as well as magnesium and iron the median intake of all groups is adequate and lies above the German recommendations. For Vitamins D and B12 as well as zinc none of the groups reach the recommended intakes. Those participants following an omnivore RFD come closest to the recommended intakes for Vitamin B2 and calcium. For Vitamins A, B6, D and the minerals magnesium and iron a statistically significant difference between omnivore and vegetarian intakes could be shown; the vegetarians having the lowest median intake for all these other than iron.

 

Table 4: Median daily nutrient intake of omnivore, vegetarian and vegan participants as well as German recommendations

nutrients p2,3

omnivore
(n = 56)

p2,4

vegetarian
(n = 90)

p2,5

vegan
(n = 55)

DGE DGE
    median 90% CI   median 90% CI   median 90% C women1 men1
nutrient energy (kcal) 0,0126 2117 1317-3858 0,0026 1852 962-3271 0,9837 1899 568-3365

2000/
1800

2400/
2200

vitamin A
(mg RE)

0,1965 2,8 0,8-8,8 0,0401 2,0 0,6-5,4 0,8132 2,4 0,3-7,6 0,8 1,0
retinol
(m g)
0,0000 121 3,0-1602 0,0110 65 1,6-287 0,0000 0,0 0,0-3,2    
β-carotin (mg) 0,5013 15 3,5-51 0,1040 11 3,0-32 0,4783 15 1,9-46    
vitamin D (m g) 0,0736 4,4 0,2-23 0,0164 2,9 0,1-14 0,7957 3,2 0,0-31

5

vitamin E (mg) 0,2027 21 12-51 0,0894 19 9,6-39 0,9286 19 3,8-41

12

vitamin B2 (mg) 0,0087 1,8 0,9-3,5 0,0037 1,4 0,9-2,5 0,8449 1,4 0,4-2,8 1,6 1,9
vitamin B6 (mg) 0,0675 3,7 1,9-6,4 0,0035 2,8 1,6-5,2 0,4151 3,0 0,9-7,5 1,6 1,8
vitamin B12 (m g) 0,0000 1,4 0,3-29 0,0000 0,3 0,0-5,2 0,0000 0,0 0,0-0,2

3,0

vitamin C (mg) 0,5051 496 159-1231 0,1440 439 203-832 0,6364 424 102-1448

75

magnesium (mg) 0,2266 646 370-1204 0,0092 570 352-944 0,3678 618 104-1253 300 350
calcium (mg) 0,0768 831 421-1542 0,1418 732 467-1449 0,4058 714 151-1387

900/800

iron (mg) 0,0850 21 11-39 0,0375 18 12-32 0,9286 18 5,2-33 15/10 10
zinc (mg) 0,0031 9,9 5,7-24 0,0166 8,6 5,3-21 0,1748 8,1 1,7-18 12 15
1 recommendations for adults aged 25-51/51-65
2 Test of significance according to Mann-Whitney (U-test) between 3 omnivore and vegan, 4 omnivore and vegetarian,
5 vegetarian and vegan

not significant

p < 0,05

p < 0,01

p < 0,001

 

Discussion

The participants are characterised by a higher health awareness, as is often observed in studies of persons following alternative dietary regimens. Considering that many fast and that the median nutrient energy intake is lower than recommended, it seems possible that some of the participants will be in a state of hunger metabolism. Since fruit is by far the major component of the RFDs, it is also often the primary nutrient source. This means that the intake of nutrients that are usually provided by cereal products and/or foods of animal origin such as vitamins B12 and D, and the minerals zinc and calcium is insufficient. On the other hand, the intake of certain protective nutrients, such as Vitamin C and other antioxidants, lie above the national average. The data show that an almost exclusive consumption of raw fruit and vegetables bear some advantages for nutrient intake but also may carry the threat of serious deficiencies. These findings need to be verified by analyses of nutrient status, a further aspect of this study which is currently under way.

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