The New York Times (NYT) is a great source of articles on diet and weight loss.
A recent NYT article* discusses a number of issues that the author and others, including Oprah Winfrey, have faced over the years in dieting and weight loss attempts.
*Losing It in the Anti-Dieting Age: The agonies of being overweight — or running a diet company — in a culture that likes to pretend it only cares about health, not size. BY TAFFY BRODESSER-AKNERAUG. 2, 2017
Ms. Brodesser-Akneraug discusses commercial diets as well as an eating strategy called Intuitive Eating.
For a reference on commercial diets like Weight Watchers see Resource (1) which concludes:
Clinicians could consider referring patients with overweight or obesity to Weight Watchers or Jenny Craig. Other popular programs such as NutriSystem show promising weight loss results; however, additional studies evaluating long-term outcomes are needed.
Resource (2), Hunger Can Be Taught, is very interesting. The article uses blood glucose monitoring to help determine when it is time to eat. Here are some excerpts:
Background
The effects of positive energy balance are well known and underlie the great scourges of Western industrialized nations including obesity, diabetes, and heart disease. More than 1.1 billion adults worldwide are OW, and 312 million of them are obese;1 obesity has been shown prospectively to be associated with dietary and lifestyle factors.2 Dieters’ inability to lose weight long term by restraining food intake (dietary restraint) is well known.3 . . . . A system for regulating nutrient intake that does not involve dietary restraint is called for.
Identifying hunger
To help people recognize whether they are indeed physiologically hungry, two complementary lines of enquiry were independently followed. Lovell-Smith et al sought to define the subjective hunger experience precisely and hence help people to differentiate between hunger and other experiences.17 Building on the early work of Cannon and his contemporaries, hunger was identified as two sets of subjective experiences. The first is the Empty Hollow Sensation (EHS). This corresponds to Cannon and Washburn’s hunger pang, is a physical sensation experienced in the epigastrium, and indicates readiness to digest.18 This physical epigastric sensation is associated with Phase III contractions of stomach and duodenum.19
The second subjective physical experience often associated with hunger is termed inanition. This includes fatigue, light-headedness, and general weakness. Inanition is taken to indicate the need for nutrition, but not necessarily readiness to digest. As indicated above, both the EHS and inanition are accompanied by, but are distinct from, appetite, the desire to eat. The desire to eat, when it occurs in the absence of EHS or inanition may be prompted by any of the confounding intrinsic or extrinsic stimuli alluded to in the above introduction. The term IH was coined by author MC and is either EHS or inanition at their first appearance. IH correlates well with BG below about 81.8 mg/dL (4.54 mmol/L).21 These two approaches to the study of hunger, subjective clarification, and the discovery of an objective marker overlap and are mutually supportive.
The relationship between hunger and BG Transient declines in BG pre-meal are well recognized,22–24 and BG decline is associated with hunger.25 Glucose has long been considered a prime candidate in the regulation of energy metabolism, being an exclusive energy source for the central nervous system and having limited storage, high turnover rate, and tight regulation.The initiation of hunger and eating behavior is the result of a complex interplay between genetic, psychological, neurological, biochemical, and hormonal factors. Early single factor depletion models such as the glucostatic hypothesis of Mayer26 in which it is assumed that all physiology and behaviors seek to maintain a stable glucose have given way to models that recognize this interplay. Nevertheless, BG is a useful metabolic marker in training subjects to recognize hunger. BG is taken to indicate the body’s supply of readily available nutrients and their ability to quickly provide energy to body tissues. In a physiologically normal, nondiabetic population, BG therefore indicates the dynamic state of energy balance. High BG indicates immediate positive energy balance, while low BG indicates immediate negative energy balance.
Although patients can be trained to recognize hunger without concomitant BG measurement, it is more difficult.
Concurrent BG measurement provides an objective standard against which subject and trainer/therapist can assess the correspondence of future interoceptive sensations. This is helpful in building confidence in those sensations that subjects are learning to interpret as hunger, it helps “slow learners” to find the relevant sensations more readily, it gives the trainer/therapist an objective “window” into the subject’s internal world, it helps the trainer/therapist assess compliance, and helps subjects to correct occasional errors of perception even months or years after training. All formal studies reported here have used the concurrent BG method of training.
Adult studies
Correlation of IH and BG
The method used in all reports is detailed here. Subjects were asked to withhold food intake for a few hours, and make note of the physical sensations that they experienced and which they associated with the need for food intake. The EHS was the most frequent and recognizable sensation, followed by inanition. After determining their symptoms, subjects were trained to measure their own BG by portable glucometer and thus learned to associate these sensations with BG concentration. Subjects were encouraged to eat only when the sensations of IH were present. The principal investigator phoned each subject at the end of the first day of training to ascertain any changes made by the subject in eating pattern. A mean delay of 2 hours (range 0–48 hours) in meal intake was noted on the first day of training. At subsequent mealtimes, adults evaluated their physical sensations according to the BG-correlated experience to help them assess if their present sensation was indeed hunger or whether their desire to eat was conditioned by time of day or other extrinsic factor. Subjects were encouraged to become familiar with the hunger sensation and to take a meal only at its first appearance (see Appendix).
The effectiveness of this method in altering eating habits needs to be spelled out to be fully appreciated. In effect, subjects stopped eating “automatically.” This means that they stopped eating according to extrinsic cues and began eating according to their intrinsic interoceptive awareness of hunger. The method encourages subjects to make a judgment on the amount to be eaten such that hunger will appear at the next mealtime. This is a radically different approach to other systems of dietary instruction in which emphasis is laid upon feelings of satiety. In the authors’ experience, subjects find instructions such as “stop before you feel full” and the like restrictive and disheartening. Such instructions tend to be ignored leading to excessive food intake. By contrast the instruction “start when you feel empty” invites compliance, since eating when hungry is inherently pleasurable. For most subjects at the beginning of training, a meal intake of 150 kcal for infants and 300 kcal for adults ensured hunger at the subsequent mealtime, with adjustments spontaneously made in either increasing or decreasing energy-dense food to reach IH at the desired time. In spite of a generally lower caloric intake subjects reported normal activity and did not report lowered energy during the intermeal period.
Subjects received information on food energy content, recommended vegetable intake, and physical activity per day. The recommended fruit and vegetable amount for adults was 1 kg/day. The investigators recommended avoiding high ambient temperatures and wearing excessive clothing as these tend to slow metabolic rate and delay the appearance of hunger sensations. They also encouraged normal outdoor and gym activities. Avoiding snacks was suggested, though earlier than optimal IH was satisfied with fruit and adequate energy-dense food if needed. Social obligations such as parties and school catering were included in planning the intake amount and timing of the previous and subsequent meals.
Interaction between expert and subject was necessary for most subjects to interrupt automatic feeding and to stop any reliance on fullness sensations toward meal end. The process generally became “second nature” after a few days. The subject realizes that IH will arise at the desired times when intake is accurately judged. The intervention may be summarized as an effortless cessation of automatic feeding and its replacement by an informed judgment on the amount to be eaten.
Establishment of a hunger-based meal pattern
Once the subjective sensation of hunger has been recognized,
the measurement of BG functions as an objective marker
against which the subject can check ongoing pre-meal
subjective sensations. It should be noted that subjects are not
asked to wait until BG is low or at its nadir before checking
their hunger sensations. On the contrary, the subject first
notes the subjective experience then checks it against BG.
BG acts to clarify, verify, and validate what might otherwise
remain as undifferentiated interoceptive sensations.
After a few days of trial and error and sometimes irregular
mealtimes, MC found subjects were able to arrange their
meal size and composition to ensure that IH appeared just
prior to the following meal-time with a mean error of half an
hour in 80% of adults and 90% of children. This is the pattern
of food intake that has been called the IH Meal Pattern.
The next step was to investigate the metabolic consequences
of sustained application of this meal pattern. The initial aim
was to see whether by creating immediate blood energy balance
(avoiding food intake in the presence of high BG and taking
food only in the presence of low BG) it would be possible to
balance total body energy intake to energy requirement long
term, ie, to achieve total body energy balance as shown by
neither increase or decrease of body weight in NW subjects
and loss of weight in OW subjects, over a period of months.35Weight
Hunger Recognition was associated with significant decreases in body weight and body mass index (BMI) in OW subjects compared to controls after 7 weeks of training and after 3 further months of application. BMI decreased from 28.7 ± 3.5 to 26.5 ± 3.5 in the trained group.
Insulin sensitivity
Hunger Recognition was associated with significant decreases in insulin and BG peaks, insulin at 60 minutes and 90 minutes during the glucose tolerance test, glycosylated hemoglobin, and mean pre-meal BG as well as energy intake and BMI when compared to controls. Insulin sensitivity index increased from 7.1 ± 4.1 to 9.4 ± 5.2. The increase was significant in comparison to controls (P , 0.01) and in comparison with baseline values of the same group (P , 0.001).
Post hoc analysis
In the latter study it was noticed that at recruitment mean pre-meal BG ranged from 64.5 mg/dL to 109.9 mg/dL. This wide distribution suggested that the overall improvement in insulin sensitivity at study end could be mostly accounted for by improvements in those subjects whose pre-meal BG was high at recruitment. Furthermore, it was noted that for the week in which each subject kept a diary of pre-meal BG, the mean confidence interval (95%) around that subject’s mean pre-meal BG was only ± 3.84 mg/dL. Thus, although subjects differed widely from each other in BG concentration pre-meal, their own individual pre-meal BG concentration varied little. This suggests that many people eat at an arbitrary BG, not necessarily according to homeostasis and more likely associated with habit. For many subjects, energy intake was habitually high and was
likely leading to positive energy balance. Other subjects were
already eating at low BG concentration and thus probably
already eating more or less according to homeostasis.
To test this, the effect of Hunger Recognition on each of
two subgroups – those who at recruitment were found to
eat habitually at a high blood glucose concentration (high
BG) and those who at recruitment habitually ate at a low
blood glucose concentration (low BG) – was analyzed. The
demarcation point that divided the two groups was a mean
pre-meal BG concentration of 81.8 mg/dL (4.54 mmol/L).
This was the BG value that statistically most significantly
divided the two groups.Variation in mean pre-meal BG among trained low BG and high BG subjects
High BG trained subjects significantly decreased their mean pre-meal BG (n = 55; pre: 91.6 ± 7.7 mg/dL; post: 81.0 ± 7.7 mg/dL; P , 0.0001; Figure 3). Among low BG trained subjects (n = 34) pre-meal BG remained relatively constant (pre: 76.6 ± 3.7 mg/dL; post: 77.2 ± 4.2 mg/ dL; P = 0.499). Trained high BG but not low BG subjects showed a cumulative energy balance that was negative over the 5 months of the study as indicated by measurement of skin-fold thickness. Furthermore, trained high BG but not low BG subjects showed decreased insulin area under the curve, an index of whole body insulin resistance, decreased glycosylated hemoglobin, and increased insulinogenic index,37 suggesting that low pre-meal BG is physiologically appropriate for energy needs. Only those subjects whose energy intake (and BG) was high at recruitment adjusted their food intake after training. Those for whom energy intake was already low made little or no adjustment. These data are consistent with homeostasis and support the notion that the observed effects could be accounted for mainly by the effect of the intervention on the high BG trained subjects.
Conclusion
The last 60 years have seen huge effort towards teasing out the physical, neurological, and biochemical pathways that regulate food intake and energy balance. The motivation generally is to discover drugs that will help foster energy balance. While unraveling physiological complexities has its own fascination, the solution to achieving energy balance may be as simple as asking people to wait before they eat until they experience objectively validated hunger.
Resources:
(1) Efficacy of commercial weight-loss programs: an updated systematic review [PubMed Abstract] [Full Text HTML] [Download Full Text PDF]. Ann Intern Med. 2015 Apr 7;162(7):501-12. doi: 10.7326/M14-2238.
(2) Hunger can be taught: Hunger Recognition regulates eating and improves energy balance [PubMed Abstract] [Full Text HTML] [Download Full Text PDF]. Int J Gen Med. 2013 Jun 17;6:465-78. doi: 10.2147/IJGM.S40655. Print 2013.
(3) Adherence to hunger training using blood glucose monitoring: a feasibility study [PubMed Abstract] [Full Text HTML] [Full Text PDF]. Nutr Metab (Lond). 2015; 12: 22.
Published online 2015 Jun 9. doi: 10.1186/s12986-015-0017-2
