The initials “FHB” stand for “family hold back.” When guests (especially unexpected guests) were served dinner and there was not enough food to go around, the family members would tell each other “FHB” (“family hold back”), a secret code not to ask for seconds.
 
However, if there was more than enough food to go around, the family’s secret message was “MIK” (“more in kitchen”), meaning that there was more food in the kitchen and the family could keep on eating.
 
“FHB” was printed in a story from about March 1898 in the Boston (MA) Traveler that was widely reprinted that year. The family using “FHB” was from West Philadelphia. “MIK” is cited in print from at least 1906.
 
The initials “FHB” and “MIK” are mostly nostalgic today, but are still remembered by many. With “FHB” and “MIK” so well known for over a century, does it still work as a “secret code”?
 
     
9 March 1898, Freeborn County Standard (Albert Lee, MN), pg. 13, col. 6: 
HOSTESSES’ SECRET SIGNAL.
Tip to the Family If There Is Not
Enough to Go Around.
Nervous housewives whose husbands frequently bring home company to dinner without preliminary warning often worry in their secret hearts to supply the unexpected guests. A matron living in one of the prettiest suburban residences in West Philadelphia, whose husband persists in bringing home guests at the most inopportune times, has hit upon a happy expedient to meet possible emergencies.
 
In passing any dishes at the table of which there may be a limited supply the hostess makes a point to mention the enigmatical letters, F. H. B. in such a manner as not to attract the attention of the guests around the board. Immediately the members of the family are aware of the circumstances, and discreetly partake very lightly, if at all, of the viands in question, The secret of the three letters was solved a few days ago, and the hostess afterwards laughingly confessed her little scheme. “F. H. B.” in this instance stands for family hold back.
 
17 March 1898, Daily Oklahoman (OK), pg. 2:
HOSTESSES’ SECRET SIGNAL.
Tip the Family If There Is Not Enough
to Go Around.
Nervous housewives whose husbands frequently bring home company to dinner without preliminary warning often worry in their secret hearts to supply the unexpected guests. A matron living in one of the prettiest suburban residences in West Philadelphia, whose husband persists in bringing home guests at the most inopportune times, has hit upon a happy expedient to meet possible emergencies.
 
In passing any dishes at the table of which there may be a limited supply the hostess makes a point to mention the enigmatical letters, F. H. B. in such a manner as not to attract the attention of the guests around the board. Immediately the members of the family are aware of the circumstances, and discreetly partake very lightly, if at all, of the viands in question, The secret of the three letters was solved a few days ago, and the hostess afterwards laughingly confessed her little scheme. “F. H. B.” in this instance stands for family hold back.
 
Chronicling America
10 June 1898, Gulf Coast Breeze (Crawfordville, FL), “Her Sscret Signal,” pg. 6, col. 5:
Nervous housewives whose husbands frequently bring home company to dinner without preliminary warning often worry in their secret hearts to supply the unexpected guests. A matron living in one of the prettiest suburban residences in West Philadelphia, whose husband persists in bringing home guests at the most inopportune times, has hit upon a happy expedient to meet possible emergencies.
 
In passing any dish at the table of which there may be a limited supply the hostess makes a point to mention the enigmatical letters, F. H. B. in such a manner as not to attract the attention of the guests around the board. Immediately the members of the family are aware of the circumstances, and discreetly partake very lightly, if at all, of the viands in question, The secret of the three letters was solved a few days ago, and the hostess afterwards laughingly confessed her little scheme. F. H. B., in this instance stands for family hold back.—Boston Traveler.
 
3 November 1903, Bellingham (WA) Herald, “F. H. B.,” pg. 3:
A guest visiting a family containing a number of children was frequently puzzled at a meal-time by hearing one or other member of the household murmur, in a warning tone, “F. H. B.” Finally his curiosity became so acute that he asked his host what the saying meant.
 
“It means,” replied the head of the household, smilingly, “that it isn’t safe to ask foir a second helping, or to accept if one be offered—that there isn’t any more of that particular dish in the kitchen.”
 
“I see,” returned the partially enlighteneed guest. “But what is the exact significance of those three letters?”
 
“They stand,” said the host, for ‘Family, Hold Back.’”—Women’s Home COmpanion.
   
7 February 1904, New York (NY) Times, “The Man in the Street,” pg. 25:
THE REV. DR. JOHN BALCOM SHAW, pastor of the West End Presbyterian Church, declares that the most interesting family he had ever seen had as its head an ex-football player on a champion Princeton team. He has arranged a system of signals, perfectly understood by a group of children affectionately calling him “Dad.” Dr. Shaw could not make out the signals. Two he recalled later and solved.
   
Just after grace the father of the flock said: “F. H. B.,” and while Mr. Shaw ate, the young man talked about many things and hardly touched his food.  Every once in a while Dr. Shaw would hear the young wife say to a child that seemed ravenous, “F. H. B.” The visitor did not happen to be very hungry, and was soon through. Then came the signal, “F. P. I.” Conversation lagged and the food disappeared.
   
Just before Christmas Dr. Shaw was in a market where he saw a particularly fine turkey.  He received an inspiration. “F. H. B.” must be “family hold back,” and “F. P. I.”  “family pitch in.” The turkey was expressed to the New Jersey clergyman football player, and tacked to it was Dr. Shaw’s card, with large letters on it: “F. P. I.”
   
A few days later he received a note signed by his friend and bearing the letters:
   
“C. S. T.  N. T. L.  F. P. I.”
   
This Dr, Shaw interpreted as meaning:
   
“Children send thanks. No turkey left. Family pitched in.”
(An illustration of a bird with the sign “F.P.I.” is on the page—ed.)
 
26 August 1906, Baltimore (MD) American, “Here and There, By the Rambler,” pg. 35:
When the Rambler told the Lady of the House about the newest woes of the Suburbanite, the L. of the H., as usual, had her story to tell of the woes of her friend, the wife of another Suburbanite. The continual happening of the unexpected in the shape of visitors and the impossibility of always being prepared for them, was the theme of her discourse. “You know, Helen is one of the most hospitable women in the world,” the Lady of the House remarked, “and she and her daughters have no end of friends. They rarely are without visitors, some of whom are invited, while the rest just ‘drop in.’ She told me the other day, when I met her in town shopping, that though she makes provision for a number of extra people besides the regularly invited guests, in her arrangments for the table, half the time she is almost driven to nervous prostration for fear the soup or the salad or the cake, or something else on the table, won’t hold out. It has gotten to such a point now that the family has devised a regular code by which the members are informed, or warned, if necessary, of the true state of the larder. When the supply is low Helen remarks ‘F. H. B.,’ which may be jumbled together until it sounds like a quotation from Kipling, but which the family all know means ‘family hold back.’ If the opposite is true, she substitutes ‘M. I. K.’ instead and the family know that means ‘more in the kitchen.’ To crown her troubles half the time she has been without a cook.”
 
“That gives her a chance to earn the degree of C. C.,” interrupted the Rambler.
 
“You mean competent cook, I suppose,” the Lady of the House answered. “Helen earned that long ago, but what I think she is entitled to is that of M. S.”
 
“What’s that?” the Rambler asked, meekly.
 
“Mistress of the Situation,” retorted the Lady of the House.
 
3 September 1908, Belleville (IL) News Democrat, “The Kitchen Cabinet,” pg. 8:
“FAMILY HOLD BACK.”
MY FIRST trip down to Auntie’s was
A trying situation,
Because of the peculiar style
Of their communication.
 
For instance, when the eggs were passed,
“F. H. B.” one would say,
Or Aunt Jemima would put in
“Don’t worry, ‘M. I. K.’”
 
Now Auntie serves up left-overs,
The best you ever tasted,
She fixes up the odds and ends
So nothing will be wasted.
 
So they explained that, when of such
There ever is a lack,
They say “Now ‘F. H. B.’” and then
The Family Hold Back.
 
But sometimes there is plenty left,
And then my Aunt will say,
“More in the kitchen,” or instead,
She’ll murmur “M. I. K.”
 
28 August 1911, Tucson (AZ) Daily Citizen, “Signals for Husbands” by Frances L. Garside, pg. 2:
“We had company recently. ‘That is F. H. B. cake,’ I said, passing it. Daysey Mayme and Chauncey Devere took the signal and refused it, but Lysander John took slices!
 
“‘What,’ asked a guest, ‘does F. H. B. stand for?’
 
“Before I could invent a name, such as French Home Baked, or Flemish Honeyed Bun, Lysander John piped out, with his mouth filled with cake and reaching for a third slice; ‘It means Family Hold Back. Whenever Mrs. A. puts F. H. B. to anything, it means there isn’t any more in the house.’”
 
4 September 1912, Frederick (MD) Evening Post, “M. I. K.,” pg. 3, col. 3:
“M. I. K.,” said a wife to her husband as he looked with veiled inquiry at her across the table. And he immediately went on eating. “M. I. K.,” said I. “Do let me in on that!” And then it was explained that “More in the Kitchen” was a phrase invented as an opposite to “F. H. B.” or “Family Hold Back.” I for one at least had never heard of “M. I. K.” And if you think of it the letters will appeal to you as useful in more ways than one. How easily such a phrase as that could become slang for more of almost anything. Slang has come into the language more than once on slighter provocation.
     
Google Books
Dialect Notes
Published by American Dialect Society
1913
Pg. 246:
f. h. b. Family hold back:—signal to refrain from partaking since “Our will became the servant to defect.”
   
8 September 1922, Los Angeles (CA) Times, pg. II6:
“I am very well aware that the saying is ‘Family hold back,’” said Miss Foy in introducing her sister, “but I can’t do that any longer.”
  “
27 November 1922, Los Angeles (CA) Times, pg. 17 ad:
There is no danger of there being more appetite than turkey in our Thanksgiving preparations! There will be no cry of Family Hold Back!
 
21 June 1935, Los Angeles (CA) Times, pg. A10 ad:
THERE won’t be any “Family Hold Back,” when you serve Clicquot Club!
 
8 April 1938, Los Angeles (CA) Times, “Emergency Shelf Helps Housewife” by Lona Gilbert, pg. A6:
In this alphabetized day, there is one combination of letters which had mysteriously disappeared.  it is the “F.H.B.” of our childhood.  That, you remember, stood for “family hold back” and was whispered discreetly whenever unexpected guests dropped in for a meal.
 
26 April 1938, Wisconsin State Journal (Madison, WI), “Madison Day by Day” by Betty Cass, pg. 13, col. 5:
I’ve always known FHB, spoken sotto-voice at the dinner table meant “Family hold back,” but I found out only last night that MIK, intoned the same way, means “More in the Kitchen.”
 
16 May 1957, New York (NY) Times, “Topics of the Times,” pg. 30:
Abbreviations reach us at every corner today.  Probably the first that we learn is F. H. B., that whispered command from the kitchen when father brings home a few unexpected guests and “family hold back” is the only possible way by which the chicken can be made to go round.
   
8 March 1965, El Paso (TX) Herald-Post, “Polly’s Pointers” by Polly Cramer, section A, pg. 9, col. 5:
DEAR POLLY—When we have company my family uses the initials “M.I.K.” and “F.H.B.” to save embarrassment on serving seconds at mealtime. For example, we will say “Will you have some more of the M.I.K. chicken?” or “Will you have some more of the F.H.B. chicken?” If anyone asks we say these initials are the cook’s magic formula.
 
“M.I.K.” actually stands for “more in the kitchen” and “F.H.B.” says “family hold back.”—MRS. T. D. P.
 
Google Books
Family Words:
The Dictionary for People Who Don’t Know a Frone from a Brinkle
By Paul Dickson
Published by Broadcast Interview Source, Inc.
1998
Pg. 3:
F.H.B. is just the start, and there are a number of other coded dinner-table messages, including:
 
F.L.O. Family Lay Off. This is pronounced flo and is used by families that realize most of their guests already know what F.H.B. stands for.
 
M.I.K. More In Kitchen. This indicates that which there is plenty more of. It is another abbreviation like F.H.B. that has entered the language.
 
M.Y.O.B. Mind Your Own Business. This has become (Pg. 4—ed.) as popular as F.H.B., but less well known is M.Y.O.P. for Mind Your Own Plate, which is used when, for instance, one child is stealing french fries from another. M.Y.M. in a Philadelphia family is used at restaurants and other people’s dinner tables for Mind Your Manners.