Although the morphological changes in blood observed for the fasting man previously studied in this Laboratory1 were relatively slight, it seemed desirable to secure certain evidence as to the blood with the subjects of the low-diet research, so as to contribute in every way possible to the general picture of the influence of a reduced diet. Accordingly, through the kind offices of Dr. George R. Minot, the services were enlisted of Miss Anna L. Gibson and Miss Myra B. Conover, the expert technicians of the Collis P. Huntington Memorial Hospital. Blood counts were made on both squads when they came to Boston for the biweekly experiments.

Additional information regarding the possible effect of the diet upon the blood is given by the fact that at no period throughout the test did the subjects appear to the examining physician as at all anemic. He saw them, however, only under artificial light. Dr. J. H. Kellogg, of the Battle Creek Sanitarium, when at the Laboratory on the last day of the research, thought the men appeared anemic. Professor G. B. Affleck, of the International Y. M. C. A. College, who was one of the coaches and instructors and saw the men in gymnasium suits and under the best daylight conditions, also thought the men looked anemic.

As was noted in the personal histories (see p. 49), one of the subjects, Gul, donated blood for transfusions at the Springfield Hospital, the amounts being on December 23, 100 c.c; on December 29, 50 c.c; on January 6, 90 c.c; and on January 17, 50 c.c, making a total amount of 290 c.c.

The data obtained from the blood examinations in this research are given in tables 74 and 75. These values may be compared with the statement of Loewy and Zuntz, who report "asa good sign" that in their study on themselves the determinations made by the Plesch hem-oglobinometer showed for both of them 110 per cent hemoglobin.

For the interpretation of the large number of blood counts made by Miss Gibson and Miss Conover, we are very much indebted to Dr. Minot, who has been good enough to contribute the appended report:

Boston, Mass., June 18, 1918. The data on the blood examinations made by Miss Gibson and Miss Conover, both expert technicians and nurses of the Collis P. Huntington Memorial Hospital, show in general, I think, that both Squads A and B developed during the course of the experiment a definite, though slight to mild, secondary anemia. In general, it is evident that both the hemoglobin and red count are reduced, and the color index tends to be lower than normal. (Eighty-five per cent or above for the hemoglobin is normal with the Sahli instrument used.) These findings are very slight in some instances, and quite marked in others, and more evident with Squad A than Squad B. In certain instances it may be noted that instead of a progressively falling red count, there occurs a slightly increased count following a previously lower count. This may be dependent upon a temporary concentration of the blood, or dependent perhaps upon an actual increase of cells which are relatively poor in hemoglobin, as told by their histological character and the fact that the hemoglobin did not significantly rise with the increased count. The relatively slight histological abnormalities noted about the red cells, the achromia, anisocytosis, occasionally polychromatophilia, are those associated with slight or mild secondary anemia.

1 Benedict. Carnegie Inat Wash. Pub. No. 203. 1915, p. 148.

The white counts, in general, average 9,500, but little higher than normal (normal average, 7,300). With Squad B, who had not been so long on reduced diet, the white counts showed no alteration. The evidence is therefore negative so far as the white counts alone are concerned.

The white cells are evidently of the normal types, but their normal proportion is disturbed. This is evidenced by the fact that the average per cent (36) and the average absolute number (3,400) of the lymphocytes are unusually high for individuals in this vicinity, the average normal lymphocyte count being 22 per cent (though the upper normal limit may be 40 per cent) and the average normal absolute count being 1,724.1 In Squad B, in certainly 8 out of 12 cases, the lymphocytes definitely increased, both relatively and absolutely, under observation, while, though variations occur in Squad A, the average lymphocyte count is certainly well above the normal average. This increase is perhaps at the expense of polynuclear neutrophile production, for the polynuclear per cent, both squads, averages 56 per cent, which is slightly lower than the normal average, 64 per cent. However, the average absolute number of polynuclears is not so significantly altered from their normal average (4,895) as are the lymphocytes. This increase of lymphocytes is not an unusual finding in chronic secondary anemia.

The other white cells show no definite significant alteration, though in some instances the eosinophiles are very slightly more numerous than normal. Satisfactory data concerning the blood platelets, the third formed element of the blood, originating from myelogenous tissue, are unfortunately lacking. One usually finds them increased in secondary anemia, although when associated with decreased blood formation, they may become decreased.

The secondary anemia present in these cases may be dependent, perhaps, in some manner upon a decreased rate of blood formation, possibly similar to that which occurs in myxedema.

It is interesting to speculate as to what might happen to the blood of these individuals if they were kept on this same diet for a considerably longer period of time. I am inclined to believe that, under such circumstances, a greater degree of secondary anemia than the most marked case shows would probably not occur, or that it would be but very slightly greater. In other words, it seems to me that their blood would stay at a new level, one which we would interpret as a mild secondary anemia. However, I think that, if for any considerable time the blood remained at this new level, it would probably be quite difficult, perhaps impossible, for it to return to its previous normal level, and that if it did return to normal, it would probably do so very slowly. This is because, from clinical experience, the blood of cases of chronic mild secondary anemia, dependent upon various minor causes, not infrequently improves only slightly following prolonged appropriate treatment. It would seem in some such instances as if some "trap had been sprung" which could not be entirely repaired to let the completely normal hemopoetic function take place again. This may be well seen in certain rather marked and unusual cases of anemia dependent upon chronic benzol poisoning - a drug which causes an aplastic type of anemia.

George R. Minot, M. D.

1 S. R. Miller, Johns Hopkins Hospital Bulletin, 1914, 25, p. 317.

Table 74. - Rendu Of Blood Examinations During Period Of Reduced Diet - Squad A

Subject and date.

Time.

Hemoglobin. (Sahli).

Total erythrocytea.

Total leucocytes.

Polymorphonuclear neutrophiles.

Differential counts.

Eosino-philes.

Remarks on erythrocytes.

Lymphocytes.

Mononuclears.

Total.

Per cent.

Total.

Per cent.

Total.

Per cent.

Total.

Per cent.

Bro.

p. m.

p.ct.

millions.

Dec. 19, 1917..

8.20

80

4.568

8,400

5,124

61

2,520

30

756

9

...

...

Slight achromia and anisocytosis.

Jan. 12, 1918...

8.36

80

3.420

10,400

6,240

60

3,328

32

728

7

104

1

Do.

Jan. 26, 1918...

9.20

76

3.880

12,000

6,480

54

5,040

42

480

4

...

..

Considerable achromia and slight anisocytosis.

Feb. 918...

7.40

78

3.840

8,000

4,160

52

3,200

40

560

7

80

1

Slight achromia and anisocytosis.

Can.

Dec. 19, 1917...

7.20

80

3.856

14,000

9,800

70

2,940

21

980

7

280

2

Slight achromia and anisocytosis.

Jan. 12, 19181..

9.25

72

3.200

12,000

7,560

63

3,600

30

720

6

..

..

Do.

Jan. 26, 1918s..

7.45

78

3.688

7,000

3,780

54

2,380

34

630

9

140

2

Marked achromia and slight anisocytosis.

Feb. 2,1918...

7.20

72

5.080

12,800

7,424

58

4,608

36

768

6

...

..

Slight achromia.

Kon.

Dec. 19, 1917...

8.30

76

5.368

6,000

3,300

55

2,400

40

180

3

120

2

Considerable achromia and anisocytosis.

Jan. 12, 1918...

7.15

74

4.280

9,000

5,850

65

2,610

29

540

6

..

..

Do.

Jan. 26, 1918...

8.15

78

4.480

9,200

5,980

65

2,760

30

368

4

92

1

Slight achromia.

Feb. 2,1918...

8.00

78

4.832

9,600

6,144

64

2,688

28

576

6

192

2

Do.

Gar.

Dec. 19, 1917...

8.50

80

5.976

16,000

7,200

45

6,560

41

1,280

8

960

6

Slight achromia, polychromatophilia and anisocytosis.

Jan. 12, 1918...

8.35

70

4.621

9,600

4,128

43

4,512

47

576

6

384

4

Slight achromia and anisocytosis.

Jan. 26, 1918...

8.55

73

4.328

10,000

5,400

54

4,000

40

500

5

100

1

Do.

Feb. 2,1918...

8.20

70

4.132

7,200

4,320

60

2,592

36

288

4

..

..

Do.

Gul.

Dec. 19, 19173..

7.20

74

5.728

10,800

5,508

51

3,780

35

1,080

10

324

3

Slight anisocytosis.

Jan. 12, 1918...

9.05

76

4.480

10,800

5,940

55

3,888

36

432

4

540

5

Considerable achromia.

Jan. 26, 1918...

9.05

78

4.288

8,600

4,902

57

2,580

30

688

8

430

5

Slight anisocytosis.

Feb. 2,1918...

8.20

75

4.160

8,000

3,840

48

3,680

46

480

6

..

..

Slight achromia and anisocytosis.

Mon.

Dec. 19, 1917...

9.10

75

4.240

9,000

4,950

55

3,150

35

630

7

270

3

Considerable achromia and anisocy-tosis.

Jan. 12, 1918...

8.05

70

4.416

11,200

4,928

44

5,488

49

448

4

336

3

Do.

Jan. 26, 1918...

8.35

80

4.536

8,800

4,752

54

3,520

40

528

6

..

..

Normal.

Feb. 2,1918...

7.40

76

4.132

8,000

4,960

62

2,800

35

240

3

..

...

Slight achromia.

Mot.

Dec. 19, 1917...

8.10

80

5.040

12,800

6,912

54

4,224

33

1,280

10

384

3

Considerable achromia and anisocy-tosis.

Jan. 12, 1918...

7.40

80

4.924

8,800

5,544

63

2,640

30

352

4

264

3

Normal.

Jan. 26, 1918...

7.25

81

4.400

8,200

4,428

54

3,116

38

328

4

328

4

Do.

Feb. 2, 1918...

7.00

80

4.960

12,000

6,240

52

4,560

38

720

6

480

4

Do.

Pea.

Dec. 19, 1917...

9.00

72

4.880

10,600

5,300

50

4,134

39

742

7

424

4

Considerable achromia and anisocy-tosis.

Jan. 12, 1918...

8.05

72

3.840

9,600

4,800

50

3,840

40

576

6

384

4

Do.

Jan. 26, 1918...

7.25

78

4.280

8,000

4,000

50

3,280

41

480

6

240

3

Slight achromia and anisocytosis.

Feb. 2,1918...

8.00

75

3.680

8,000

4,480

56

2,880

36

320

4

320

4

Do.

Pec.

Dec. 19, 1917...

7.50

88

6.840

9,000

4,770

53

3,150

35

900

10

180

2

Slight anisocytosis.

Jan. 12, 1918...

7.15

86

4.456

5,400

2,592

48

2,484

46

324

6

..

..

Normal.

Jan. 26, 1918...

9.40

78

4.664

8,000

4,000

50

3,600

45

400

5

...

...

Do.

Feb. 2,1918...

7.20

76

4.000

8,200

5,576

68

2,132

26

410

5

82

1

Slight achromia.

Tom.

Dec. 19, 1917...

8.00

70

4.400

8,000

4,400

55

2,560

32

560

7

480

6

Considerable achromia and anisocytosis.

Jan. 12, 1918...

9.05

66

5.120

8,800

4,840

55

3,432

39

264

3

264

3

Do.

Jan. 26, 1918...

9.36

78

5.160

12,800

7,168

56

4,608

36

768

6

256

2

Normal.

Feb. 2,1918...

7.00

80

4.508

12,800

7,488

59

4,512

35

544

4

256

2

Do.

Vea.

Dec. 19, 1917...

8.40

92

4.408

7,000

3,920

56

2,170

31

420

6

490

7

Slight achromia.

Jan. 12, 1918...

7.40

60

4.496

6,600

3,300

50

2,640

40

462

7

198

3

Slight achromia and anisocytosis.

Jan. 26, 1918...

8.15

64

4.608

7,200

4,104

57

2,376

33

576

8

144

2

Considerable achromia and anisocytosis.

Feb. 2,1918...

8.35

70

4.000

8,000

4,240

53

3,040

38

480

6

240

3

Considerable achromia and slight anisocytosis.

Average...

76

4.504

9,460

5,245

55

3,409

36

576

6

222

2.3

1 Mast cells, 120 or 1 per cent.

2 Mast cells, 70 or 1 per cent.

3 Mast cells, 108 or 1 per cent.

Table 75. - Results Of Blood Examinations - Squad B

Subject and date.

Time.

Hemoglobin.

(Sahli).

Total erythrocytes.

Total leucocytes.

Polymorphonuclear neutrophiles.

Differential counts.

Eosino-philes.

Remarks on erythrocyte*

Lympho-cytes

Mono-nuclears

Total.

Per cent.

Total.

Per cent.

Total.

Per cent.

Total.

Per cent.

Fis.

p. m.

p.ct

millions.

Jan. 5. 19181. .

7.45

86

5.754

8,000

4,000

50

2,720

34

800

10

320

4

Normal.

Jan. 13. 19182 ..

6.50

85

4.842

12,800

8,192

64

3,968

31

384

3

128

1

Do.

Jan. 19, 1918...

7.40

85

5.216

10,400

5,200

50

4,680

45

520

5

....

....

Do.

Jan. 27. 1918...

7.15

87

5.336

5,600

2,800

50

2,240

40

504

9

56

1

Do.

Ha*.

Jan. 5, 19182 . .

8.00

80

4.200

9,600

5,856

61

2,640

27.5

960

10

48

0.5

Normal.

Jan. 13. 1918...

7.40

80

4.401

9,600

4,896

51

3,840

40

192

2

672

7

Do.

Jan. 19, 1918...

7.40

78

3.520

9,200

4,876

53

3,680

40

276

3

368

4

Slight achromia.

Jan. 27, 1918...

7.55

82

3.360

10,000

6,000

60

3,500

35

400

4

100

1

Do.

How.

Jan. 6. 1918...

8.40

95

5.160

8,000

4,800

60

2,400

30

720

9

80

1

Normal.

Jan. 13, 1918...

7.40

85

4.120

6,000

3,840

64

1,860

31

240

4

60

1

Slight anisocytosis.

Jan. 19. 1918...

8.20

72

4.288

8,000

4,480

56

3,200

40

320

4

..

..

Slight anisocytosis and achromia.

Jan. 27, 1918...

8.40

85

4.320

8,800

4,224

48

3,960

45

616

7

..

...

Normal.

Ham.

Jan. 5,1918...

8.24

90

4.576

8,000

4,960

62

2,240

28

560

7

240

3

Normal.

Jan. 13, 1918...

6.50

90

4.680

8,200

5,084

62

2,460

30

492

6

164

2

Do.

Jan. 19, 1918...

6.50

78

4.512

8,800

4,752

54

3,520

40

264

3

264

3

Slight achmroia.

Jan. 27, 1918...

7.35

87

5.496

7,600

3,420

45

3,268

43

608

8

304

4

Normal.

Kim.

Jan 5,1918...

9.15

82

5.584

8,000

4,400

55

3,200

40

320

4

80

1

Normal.

Jan. 13, 1918...

8.40

84

4.672

8,800

4,136

47

3,784

43

704

8

176

2

Do.

Jan. 19,1918...

8.35

80

4.032

12,800

6,400

50

5,632

44

768

6

..

..

Do.

Jan. 27, 1918...

9.20

75

4.192

6,000

3,000

50

2,700

45

240

4

60

1

Considerable achromia and anisocytosis.

Lon.

Jan. 13, 1918...

8.05

80

4.000

10,600

7,844

74

2,120

20

424

4

212

2

Slight achromia.

Jan. 19, 1918...

6.50

84

3.200

8,000

5,120

64

2,400

30

320

4

160

2

Do.

Jan. 27, 1918...

1 8.20

72

5.440

8,000

4,000

50

3,600

45

400

6

..

..

Slight achromia and anisocytosis.

SCH.

Jan. 5, 1918...

9.40

91

6.016

8,800

6,160

70

2,464

28

176

2

..

..

Normal.

Jan. 13,1918...

8.20

80

4.800

8,000

5,440

68

2,080

26

320

4

160

2

Do.

Jan. 19, 1918...

7.15

79

3.392

6,600

4,092

62

2,112

32

264

4

132

2

Slight achromia.

Jan. 27, 1918...

8.40

80

3.760

6,000

3,600

60

2,100

35

300

5

..

..

Slight achromia and aniaocytosis.

Liv.

Jan. 5, 1918...

7.45

85

6.400

10,000

7,000

70

2,400

24

600

6

..

..

Normal.

Jan. 13, 1918...

8.20

82

5.666

9,600

6,144

64

2,688

28

576

6

192

2

Do.

Jan. 19,1918...

8.20

80

4.692

11,200

6,720

60

3,360

30

672

6

448

4

Do.

Jan. 27, 1918...

82

4.000

9,000

5,220

58

3,330

37

450

5

..

..

Do.

Sne.

Jan. 5, 1918...

9.40

79

6.656

8,000

5,040

63

2,400

30

480

6

80

1

Normal.

Jan. 13, 1918...

8.40

78

4.772

8,800

5,104

58

3,344

38

352

4

..

..

Slight achromia.

Jan. 19,1918...

8.00

75

4.608

10,400

6,448

62

3,536

34

208

2

208

2

Slight achromia and aniaocytosis.

Jan. 27, 1918...

7.55

75

4.280

5,200

3,016

58

1,768

34

312

6

104

2

Considerable achromia.

Tho.

Jan. 5, 19184...

9.15

92

5.892

10,000

6,600

66

2,200

22

1,000

10

100

1

Normal.

Jan. 13, 1918...

7.15

90

4.400

8,000

4,480

56

2,720

34

640

8

160

2

Do.

Jan. 19, 1918...

8.00

85

4.320

10,000

6,000

60

3,600

36

200

2

200

2

Do.

Jan. 27. 1918...

8.20

87

5.056

8,000

4,560

57

3,120

39

320

4

Do.

Van.

Jan. 5,1918...

8.24

88

5.480

9,000

5,670

63

2,610

29

540

6

180

2

Normal.

Jan.13,1918...

8.05

85

4.920

8,800

5,016

57

3,168

36

352

4

264

3

Do.

Jan. 19, 1918...

9.00

80

4.056

7,200

4,320

60

2,160

30

576

8

144

2

Do.

Jan. 27,1918...

7.35

76

4.800

8,000

4,800

60

2,720

34

320

4

160

2

Slight achromia and anisocytosis.

WlL.

Jan. 5,1918...

8.40

86

5.000

12,800

7,168

56

4,480

35

768

6

384

3

Normal.

Jan. 13, 1918...

7.15

70

4.128

8,800

5,192

59

2,904

33

440

5

264

3

Considerable achromia and anisocytosis.

Jan. 19, 1918...

7.15

73

4.160

10,400

6,136

59

3,328

32

780

7.5

156

1.5

Slight achromia and anisocytosis.

Jan. 27, 1918...

9.00

80

4.720

6,400

3,712

58

2,304

36

384

6

Normal.

Averages:

Normal diet -

Jan. 5, 1918..........

87

5.520

9,100

5,605

61

2,705

30

629

7

137

1.5

Reduced diet -

Jan.13-27,1918.......

81

4.446

8,600

4,952

57

3,077

36

421

5

148

1.7

1 Mast cells, 160 or 2 per cent.

2 Mast cells, 128 or 1 per cent.

3 Mast cells, 96 or 1 per cent.

4 Mast cells, 100 or 1 per cent.