if the cause stated by McCollum was the real one. On the contrary large
amounts of milk prevented scurvy and small doses permitted it to develop.
The use of coarse materials as a preventative of constipation failed to
prevent scurvy onset. Hess and Unger found that cod-liver oil and liquid
petrolatum prevented constipation but failed to prevent scurvy.

The attack on the McCollum view continued from various quarters. Chick and
Hume in England examined his grain and milk fed series and showed that
those receiving much milk and little grain recovered while those on the
reverse diet died. They held that all guinea pigs with scurvy become
constipated regardless of the diet. They gave large quantities of dried
vegetables well cooked in water, in order to provide bulk, but this did
not prevent scurvy and neither did the use of mineral oil. Hess found that
in infants with scurvy there is a history of constipation but that while
potatoes which are not laxative cure scurvy, malt soups which are laxative
permit its development. He found that scurvy in infants is relieved by
amounts of orange juice entirely too small to have a marked laxative
action and was unable to secure cures with McCollum's artificial orange
juice. The most convincing argument was the discovery that orange juice
administered intravenously still exerted a curative action which could not
in any way be laid to its effect on constipation.

To these attacks McCollum's co-worker, Pitz, suggested a new hypothesis.
It was well known that in rats and man the intestinal flora can be changed
from a putrefactive form to a non-putrefactive type by feeding milk sugar
or lactose. If this were true, as was admitted by all, and the scurvy due
to the absorption of putrefactive products, this absorption might still be
the causal factor whether constipation was present or absent. To determine
this point he fed his guinea pigs on oatmeal to which he added a
carbohydrate diet. When the carbohydrate was lactose he was able to cure