From: altar@beaufort.sfu.ca (Ted Wayn Altar)
Subject: Re: Tofu, fat and protein
Organization: Simon Fraser University, Burnaby, B.C., Canada
Distribution: usa
Date: Thu, 20 Aug 1992 23:24:06 GMT

Jonathan Miller writes:


. . .
>Just what is the nutritional break-down on tofu? I've been hearing
>about how it is high in fat, and I am wondering if I should eat as
>much as I do (usually about 1/4 to 1/3 pound a day), especially
>because I am trying to lose weight.
> . . .

 
Below I've typed out the food composition values as published in
McCance & Widdowson's THE COMPOSITION OF FOODS, 5th edition,
1991.  One advantage of this reference is that the values for
"fat" pertain not just to triglycerides, but also include
phospholipids (e.g., lecithin), sterols (like cholesterol) and
related compounds.
 
With respect to soybeans and tofu we can see below that they do
consist of a lot of fat, but we should keep in mind that the
quality of the fat is here important.  About half of the fat is
unsaturated and only a small fraction is actually saturated.  We
should also note that soybeans are a good source of linolenic
acid.
 
Regarding your concern about weight, the general rule of thumb is
to reduce your fat intake (and maybe simple sugars if you eat of
lot if it) and begin to exercise more.  I'm afraid that I don't
see how eating a lot of tofu helps in this respect, although
given what else you might be eating 1/4 lb per day is not
necessarily too much.  Still, you could do a lot worst by eating
animal fats or meat instead of tofu (see the comparison with beef
averaged over 6 different cuts).  In any case, 1/4 lb of tofu is
about 113 grams, so the following amounts are just about what you
are consuming if you eat just under 1/4 lb of un-fried tofu each
day.
 
 
                      COMPOSITION PER 100g
      (unless otherwise indicated, quantities are in grams)
 
                      Soyabeans         Tofu           Beef
                     (boiled)         (steamed)      (cooked
                                                    average)
 
water                      64.3          85.0           25.2
protein                    14.0           8.1           11.9
fat                         7.3           4.2           62.8
carbohydrate  (includes     5.1            .7            0
     oligosaccharides)
 
kcal                       141            73          613
kJ                         590           304         2526
  fat/cal                  46%           51%          91%
 
 
total nitrogen              2.24          1.29         1.91
saturated fat                .9            .5         26.9
monunsatd. fat              1.4            .8         30.4
polyunsatd. fat             3.5           2.0          2.6
cholesterol (mg)            0.0           0.0         84
  P/F (polyunsatd/satd)     3.9           4.0           .09
 
starch                      1.9            .3          0
total sugars (g)            2.1            .3          0
dietary fiber
   Southgate method          N             .3          0
   Englyst method           6.1             N          0
 
Na  (mg)                    1              4          50
K   (mg)                  510             63         160
Ca  (mg)                   83            510          14
Mg  (mg)                   63             23          11
P   (mg)                  250             95          90
Fe  (mg)                    3.0           1.2          1.4
Cu  (mg)                     .32           .20          .14
Zn  (mg)                     .9            .7          1.4
Cl  (mg)                    3             16          56
Mn  (mg)                     .7            .4           .04
Se  (Ug)                    5               N         (2)
I   (Ug)                    2               N         (6)
 
retinol      (Ug)           0                0            N
carotene     (Ug)           6                2            N
D            (Ug)           0                0            N
E            (mg)           1.13            .95          .32
thiamin      (mg)            .12            .06           N
Riboflavin   (mg)            .09            .02           N
Niacin       (mg)            .5             .1            N
Trypt. 60    (mg)           2.2            1.3          1.9
B6           (mg)            .23            .07           N
B12          (Ug)            0               0            tr
folate       (Ug)           54              15            N
pantothenate (mg)            .18            .05           N
biotin       (Ug)          25.0              N            tr
C            (mg)            Tr              0            0
 
 
Notes:
   The Southgate values for dietary fiber are generally higher
than the NSP values (Englyst & Cummings method for total non-
starch polysaccharides) because they include substances measuring
as lignin and also because the enzymatic prepartion used lieaves
some enzymatically risistant starth in the dietary fibre residue.