Should we eat plenty of small meals, or one or two big meals during the day?
I'm trying to figure out what is optimal as far as blood sugar and stuff goes. Not really interested in personal or anecdotal accounts. Links to actual studies or articles by notable experts in the field would be great. Thanks!
Here are a few links to pro-IF studies:
Effect of intermittent fasting and refeeding on insulin action in healthy men
"This experiment is the first in humans to show that intermittent fasting increases insulin-mediated glucose uptake rates, and the findings are compatible with the thrifty gene concept."
A controlled trial of reduced meal frequency without caloric restriction in healthy, normal-weight, middle-aged adults
"Conclusions:Normal-weight subjects are able to comply with a 1 meal/d diet. When meal frequency is decreased without a reduction in overall calorie intake, modest changes occur in body composition, some cardiovascular disease risk factors, and hematologic variables. Diurnal variations may affect outcomes."
Full Paper: http://www.ajcn.org/cgi/content/full/85/4/981
Intermittent fasting dissociates beneficial effects of dietary restriction on glucose metabolism and neuronal resistance to injury from calorie intake.
"Intermittent fasting resulted in beneficial effects that met or exceeded those of caloric restriction including reduced serum glucose and insulin levels and increased resistance of neurons in the brain to excitotoxic stress. Intermittent fasting therefore has beneficial effects on glucose regulation and neuronal resistance to injury in these mice that are independent of caloric intake."
Caloric restriction increases learning consolidation and facilitates synaptic plasticity through mechanisms dependent on NR2B subunits of the NMDA receptor.
"Here we have examined the effects of maintaining mature mice on a long-term intermittent fasting diet (L-IFD). We found that L-IFD enhances learning and consolidation processes. We also assessed the long-term changes in synaptic efficiency in these animals. [...] These data provide a molecular and cellular mechanism by which L-IFD may enhance cognition, ameliorating some aging-associated cognitive deficits."
Cardioprotective effect of intermittent fasting is associated with an elevation of adiponectin levels in rats.
"It has been reported that dietary energy restriction, including intermittent fasting (IF), can protect heart and brain cells against injury and improve functional outcome in animal models of myocardial infarction (MI) and stroke. Here we report that IF improves glycemic control and protects the myocardium against ischemia-induced cell damage and inflammation in rats."
Beneficial effects of intermittent fasting and caloric restriction on the cardiovascular and cerebrovascular systems.
"Both IF and CR enhance cardiovascular and brain functions and improve several risk factors for coronary artery disease and stroke including a reduction in blood pressure and increased insulin sensitivity. Cardiovascular stress adaptation is improved and heart rate variability is increased in rodents maintained on an IF or a CR diet. Moreover, rodents maintained on an IF regimen exhibit increased resistance of heart and brain cells to ischemic injury in experimental models of myocardial infarction and stroke."
Caloric restriction and intermittent fasting: two potential diets for successful brain aging.
"In this review article we describe evidence suggesting that two dietary interventions, caloric restriction (CR) and intermittent fasting (IF), can prolong the health-span of the nervous system by impinging upon fundamental metabolic and cellular signaling pathways that regulate life-span."
Interleukin-6, C-Reactive Protein and Biochemical Parameters during Prolonged Intermittent Fasting
"Conclusion: Our results demonstrate that prolonged intermittent fasting in a model like Ramadan has some positive effects on the inflammatory status of the body and on the risk factors for cardiovascular diseases such as homocysteine, CRP and TC/HDL ratio."
Alternate-day fasting and chronic disease prevention: a review of human and animal trials
"The findings in animals suggest that ADF may effectively modulate several risk factors, thereby preventing chronic disease, and that ADF may modulate disease risk to an extent similar to that of CR. More research is required to establish definitively the consequences of ADF."
Grazing is for cattle. See Dr. Davis at http://heartscanblog.blogspot.com/search?q=frequency for this search for meal frequency. Good links to other sites.
. As I understand it, grazing or eating say 6 small meals a day causes your blood sugar and insulin to be in a constant elevated state which can lead to insulin resistance.
I doubt you are going to be able to answer this with research articles- you will be able to find some that seem to indicate that eating frequently is good and some that show fasting is good, etc. And any studies (like the one you cited) will likely be of sick Americans for short periods of time. I would try and figure out what the healthiest people who ever lived did. And if you are on this forum you believe the healthiest people are those that eat unprocessed food and otherwise follow a paleo diet. So the best evidence might be a survey of eating frequency of indigenous cultures. Let us know what you find!
Update thanks to Dexter's answer:
Cordain's take on the typical hunter-gatherer eating pattern seems to match what I have read elsewhere:
A midday meal or lunch was rarely or never consumed and a small breakfast (consisting of the remainders of the previous eve- ning meal) was sometimes eaten. Some snacking may have occurred during daily gathering, however the bulk of the daily calories were taken in the late afternoon or evening.
One more note: we don't live in ancestral societies and often need to make compromises. I find eating a large breakfast and large dinner to be easy to do without physical issues and convenient to fit into a work schedule.
I think what you'll find is that there were healthy H/G tribes who tended to eat once or twice a day, and healthy tribes who "snacked". So I'm not convinced that one way is always better than another. However, once your metabolism is damaged by Western foods, perhaps this changes the game -- lots of folks report weight loss via intermittent fasting.
An example of a "snacking" tribe is the Sng'oi of Malaysia. In the excellent book "Original Wisdom", the author -- who spent a good deal of time with the Sng'oi -- states:
"The Sng'oi ate the way nutritionists suggest people suffering from ulcers should eat: they snacked. As they wandered around during the day, they dug up a root here, picked some fruit somewhere else."
Also of note:
"The Sng'oi I knew were physically spare. They were short, maybe 5 feet tall. I never saw a fat person; they were well muscled, but sleekly so."
Im a full time Jiu Jitsu teacher and competitor, ive been Paleo for 2 weeks (i do milk derivates like raw yougurt, fatty cheesse, etc and sometimes yams and sweet popatoes). My portions are getting bigger, example 3 chicken breast with zucchinni, or 2 large beef livers with eggs and onions), and without been by the clock i have to eat something every 3 hours aprox. Following the PANU principles, i dont count my calories or quantity of a meal i just eat when im hungry like our ancestors, so i dont know if im getting any close to 2 meals a day, i see that imposible with the activity im demanding to my body. im eating 3 full meals plus 3 paleo snacks, also i do some fruits but just few when i dont have anything else. Today i ate 3 dinners!!! Since paleo my apettite had increase. any recomendations or comments? forgot to mention, just in 2 weeks im leaner, stronger, faster, and dropping weight from fat (5 pounds so far), also i feel my body with more muscle and ealthier, at the beggining of the diet i had problems pooping, but i found celery very helpfull.
I'm not adept at interpreting nutritional studies as some here are, but here's one someone cited to suggest more meals are better (or at least that we just don't know as, others have suggested): http://www.ncbi.nlm.nih.gov/pubmed/18394217
I found this in the comments from this lengthy article (I've only gotton through part 1 so far)http://anthonycolpo.com/?p=586. The article was posted in a disscussion on Panu forum and claims to refute many low-carb "myths"...
I'm interested in this question as IF does sound good, but I'm wondering if it does in fact work to control (reduce) insulin. Anecdotely, since going Paleo I do notice I am not usually as hungry in the mornings, so while I still eat 3 meals/day, breakfast is later and I don't snack as much. Would IF reduce insulin only if overall calories are fewer? Or is there something more complex happening. I do not want to lose weight, so I if I tried to fast more it would be only to reduce insulin caused by too many meals/snacking. I asked this in comments somewhere else, but is less total insulin released if the same number of calories are consumed in 1-2 meals rather than having the calories spread out in 8-10 smaller meals?
I think it depends on the individual and your goals. I found that 3 or less meals (without any significant snacks) my strength decreases and I my body composition changes. However, I know some who can live off of 2 meals a day and have the opposite results. As robb always says, how do you look, feel and perform. Since going back to at least 3 meals and a snack or 2 my "look, feel, and perform" is much better.
I believe that natural bodybuilders are some of the most knowledgeable about eliminating body fat and maintaining muscle and bone density, as a life style. I can see how a Paleolithic diet would make the lifestyle even better. I believe that knowing a persons lean mass and developing a diet that allows for the nourishment of the lean mass is necessary. I believe that over eating, per meal, especially high glycemic refined carbs and processed foods puts a body into fat storing, especially after the lean receptors are fed. The additional insulin required to clear the excess calories will end up as stored fat. Depending on the body type, muscle mass, activity level and activities that consume energy, triggered by hormones, the lean mass will need refueling every 3-4hours throughout the usual 16-17 hours of being awake, to avoid low blood sugar, which is a fat sparing mode, at the expense of lean mass, over time. This leaves us with the longest fast of the day being the sleep cycle of 7-9 hours. If, according to Dr. Udo Erasmus, the body requires 1 level Table spoon of the correctly balanced Omega 3 & 6 at the 2:1 or 3:1 ratio, then, at 120 calories per table spoon, it is easy to see that getting between 25-30% of the persons total dietary calories as fats can be easily achieved with the addition of the desirable saturated fats. If a person is to get between .5 and .9 grams of protein per standing lean mass, per day (28 grams per oz), and multiple intakes of protein throughout the day being necessary to maintain a positive protein/nitrogen balance to maintain lean mass.......and adequate water soluble vitamins and adequate vegetable intake to maintain antioxidant supplies in the blood stream, especially potassium, to keep the persons pH out of acidity......To keep this short.....Nutrition science, combined with a Paleo diet is optimal, I believe. I believe eating smaller, well balanced meals is optimal, combined with regular necessary pushing and pulling i.e weight training to create the ideal and optimal life cycle of Nutrition, Exertion and Sleep. Wolf's law in physiology states that the robustness of bone and muscle tissue is directly proportional to the force applied on a regular basis...use it or lose it. Eating and exertion are hormonal and help to set up the ideal balance of eating, maintaining lean mass (bone, organs, and muscle) and sleeping. Walking does nothing to maintain upper body lean mass and nervous system training and maintenance. Walking increases metabolic rate. Pushing and pulling maintain upper body lean mass. It's a cycle of Nutrition (and a lot of water), Exertion and Sleep. Why not understand the relationship between the 3. If one or more of the 3 are missing the results are NOT optimal. Many Paleo people forget the Exercise, muscle maintaining type, and don't get the optimal hormonal balance. 90 minutes of correct form, high intensity pushing and pulling, plus 3 sessions of 30 minutes of dedicated aerobics (220 - age X .65 -.8 = heart rate)....Dr. Ken Cooper of the Cooper Institute says anything other than 3 sessions of 30 minutes, per week, is for reasons other than health. Fat reduction is done best by correctly feeding, exerting and resting. Calories don't evaporate doing aerobics. Growth Hormone and Glucagon are the main hormones that need to be put into the blood stream to trigger fat release into the bloodstream. Glucagon comes from the pancreas and can not occur in the presence of insulin. Growth Hormone is from the Pituitary glad. REM sleep and a good hormonal balance is needed for a healthy, strong and lean lifestyle. Check it out. This isn't a new idea, this has been known for a LONG time.