The subject of high fat/high protein diets to elicit weight loss and
improve blood lipid profiles is clearly controversial in the nutritional
community.   Dean has done a wonderful job in the last listing to
highlight the salient literature which supports the concept.   Clearly,
Reaven and the group at Stanford have strong data to show that low fat,
high carb diets tend to worsen many aspects of blood lipid profiles in
both normals and in NIDDM patients.   However, to date neither they nor
any other researchers that I am aware of have evaluated extremely low
carb diets or extremely high protein diets; nor have there been any
experiments in which the macronutrients (protein, fat, CHO) have been
separated at each meal.
        The separation of macronutrients would have been a frequent  feeding
pattern for pre-agricultural modern H. sapiens and perhaps the most
frequent feeding pattern for pre-modern hominids in which there is
little evidence for storage  of goods or food ( 1  ).    Consequently,
when an animal was killed, it was entirely consumed within a 24 hr
period, similar to modern day hunter gatherers ( 2  ).    Except for
some stored hepatic and muscle glycogen, there is virtually no
carbohydrate in food derived from animal sources; therefore, protein and
fat meals tended to be consumed together.    Carbohydrate sources came
primarily from uncultivated fruits, vegetables, tubers, nuts and seeds
and tended to be consumed while they were gathered (2); consequently
carbohydrates generally were consumed separate from protein and fat.
The concept of a regular sit down meal with a wide variety of foods,
both animal and plant based would have been a rare occurrance for most
pre-modern hominids and many contemporary hunter gatherers.
        Recent data has shown that the ubiquitious high fat, high carb meal of
western societies worsens elements of the post- prandial lipid profile
more so  than simple high fat meals (3,4 ).    Consequently, it may be
that separation of macronutrients similar to our evolutionary experience
may be an effective dietary procedure to prevent some of the health
shortcomings of the traditional high fat, high carb meal of the western
world.     There was a series of popular diet books in the 1930's in the
USA which advocated exactly this eating pattern  (5,6 ).    Clearly, the
separation of fat from carbohydrate has many evolutionary clues pointing
in its direction for improving health, but to date there have been no
clinical trials evaluating this concept.

                                REFERENCES

1.  Ingold T.  The significance of storage in hunting societies. Man
1983;18:553-71.

2.   Hawkes K et al.  Why hunters gather: optimal foraging and the Ache
of eastern Paraguay. Am Ethnologist 1982;9:379-98.

3.  Chen IYD et al.  Effect of variations in dietary fat and
carbohydrate intake on postprandial lipemia in patients with noninsulin
dependent diabetes mellitus. J Clin Endocrinol Metabol 1993;76:347-51.

4.  Chen IYD et al.  Effect of acute variations in dietary fat and
carbohydrate intake on retinyl ester content of intestinally derived
lipoproteins. J Clin Endocrinol Metabol 1992;74:28-32.

5.  Hay WH.  Weight control.  London Harrap, 1936.

6.  Hay  WH.  A New Health Era.  Mount Pocono, PA, Pocono Haven, 1936.