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
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 |
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
|
p1,3 |
vegetarian
|
p1,4 |
vegan
|
|||
. | . |
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
|
p2,4 |
vegetarian
|
p2,5 |
vegan
|
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/ |
2400/ |
vitamin A |
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.