The new health guide / edited by Sir William Arbuthnot Lane.

  • Lane, William Arbuthnot, 1856-1943.
Date:
[1935]
Catalogue details

Licence: In copyright

Credit: The new health guide / edited by Sir William Arbuthnot Lane. Source: Wellcome Collection.

    39/226 (page 35)
    CHAPTER II Food and Digestion My colleague, Dr. J. Neil Leitch of the London School of Dietetics, has already dealt with the properties and sources of the principal food factors; it now remains to consider the changes which proteins, carbohydrates, and fat undergo before finally passing into the blood-stream. There are only two foods that will diffuse into the blood-stream without digestive action, viz. dextrose and alcohol. All other forms of food require to undergo a breaking-down process into final products that will either pass directly into the blood-stream through the capillary walls or into the lymphatic system via the lacteals. The final digestive product of all carbohydrate foods —e.g. starch, dextrin, milk sugar, malt sugar, and cane sugar—is dextrose in which form it diffuses into the blood capillaries, and in proteins the end factors are the amino acids. Part of the fat is emulsified and is readily absorbed by the villi and passes to the lacteals, and so enters the lymphatic system to be finally discharged into the blood-stream from the thoracic duct into the junction of the left jugular and sub-clavian veins.