Conventional wisdom often dictates that we should eat three meals a day with nothing in between. The idea here is that snacks just add to our calorie intake, and therefore can only contribute to our body weight. However, I find in practice that for successful weight management, more frequent feeding is required. Regular eating can, theoretically ‘stoke’ the metabolism, and may help temper insulin levels too [1,2] (and insulin is the chief hormone responsible for fat storage in the body).
The other thing, of course, is that regular eating can help stop the appetite running out of control. This is important because a rampant appetite can make it mightily difficult to make healthy food choices, both in terms of what and how much we eat. Put another way, snacking can make it much easier to eat healthily.
I was interested to read a study published this week which looked at the relationship between snacking and risk of being overweight [3]. The study, published on-line in the American Journal of Clinical Nutrition, found that more frequent snacking was associated with a lower risk of being overweight. Snacking was associated with a reduced risk of having excess weight around the middle too.
Now, so-called ‘epidemiological’ studies of this nature only really tell us about associations between things, and this study therefore does not necessarily indicate that snacking protects against unhealthy weight gain. It is possible, say, that individuals of healthy weight quite naturally feel less need to restrict their food intake and are more relaxed about eating snacks. Also, overweight individuals may tend to under-report any snacking they partake in.
However, it should not be forgotten that there are quite sound reasons for why snacking might genuinely help protect against weight gain (see above). Plus, there are other studies which support the notion that snacking is generally good where weight management is concerned. For example, in one study, the more regularly individuals te, the lower their body weight and fatness tended to be [4]. This association even remained after accounting for other factors that might help explain it, such as physical activity and overall food intake. In another study, individuals eating five or more times a day, compared to those eating three or fewer times each day, were half as likely to be overweight [5].
When it comes to what to snack on, I generally suggest nuts. Nuts are also a generally very nutritious food, and their consumption is associated with a reduced risk of chronic disease including heart disease. But one of nuts’ best features, I think, is their capacity to sate the appetite effectively. This contrasts with, say, fruit, which tends not to sate the appetite very well at all. The slow sugar-releasing and relatively protein-rich nature of nuts almost certainly contribute to their appetite sating properties.
Despite their ability to quell hunger effectively, nuts tend to have a reputation as a fattening food. Actually, though, the evidence suggests that nuts do not promote weight gain. Some evidence suggests they actually promote weight loss.
One reason for this is that when people eat more nuts, they often simply eat less of other foods. For more about this, see here.
References:
1. Jenkins, D J et al., ‘Nibbling versus gorging: advantages of increased meal frequency’, N Engl J Med 1989; 321(14): 929-34
2. Rashidi, M R, et al., ‘Effects of nibbling and gorging on lipid profiles, blood glucose and insulin levels in healthy subjects’, Saudi Med J 2003; 24(9): 945-48
3. Keast DR, et al. Snacking is associated with reduced risk of overweight and reduced abdominal obesity in adolescents: National Health and Nutrition Examination Survey (NHANES) 1999-2004. Am J Clin Nutr 16 June 2010 [epub ahead of print publication]
4. Ruidavets, J B et al., ‘Eating frequency and body fatness in middle-aged men’, Int J Obes Relat Metab Disord 2002; 26(11): 1476-83
5. Fabry, P et al., ‘The frequency of meals its relationship to overweight, hypercholesteremia, and decreased glucose-tolerance’, Lancet 1964; 2: 614-15
Dr. Briffa,
Your post seems to be directed to “dieters” who are trying to reduce their weight.
Surely by now, if you are following your own guidelines, you know that you don’t get the urge to snack.
When you are low carb, high fat in your eating habits, you don’t get cravings that cannot be controlled.
To miss a meal is easy.
In the transition stage I coped by eating avocado and cheese and sometimes roll mop herrings and sometimes nuts.
After a month you don’t get the uncontrollable urge to snack. If you avoid grains and sugar, and indulge in fat, you will not be needing to supplement between meals, in a relatively short time. A month.
Dr. Briffa,
I seem to have a case of atopic dermatitis that appears when I eat various types of nuts. Are there any other “snack” alternatives you suggest in cases where individuals do not tolerate nuts well for one reason or another?
i don’t think the “snacking hypothesis” is valid for everyone, if at all. as you correctly said, it *may* help prevent binge eating for some – but if so, it is probably more a fix to a symptom (instable blood sugar levels) caused by a suboptimal eating approach anyways. also, some very well trained athletes and/or (natural) bodybuilders follow a eating pattern called intermittent fasting and/or compressed feeding window, where one abstains from eating voluntarily for up to 16h (usually) before training, and still (or rather, because of that) is able to maintain a very high muscle vs. fat mass ratio. so, snacking is def. not NEEDED to maintain low body fat or good health if the rest of the nutritional aspects is well designed. there might be some statistical correlation, but that proves exactly nothing, as you know.
Robert
How about seeds?
Qualia
Snacking may not be needed by some people for healthy weight maintenance. However, it ca very hugely useful and beneficial for others. Even when individuals eat healthily, some can struggle to go for many hours without eating. The rampant hunger this can induce can make eating healthily very challenging. For many, healthy snacking makes healthy eating so much easier and more sustainable.
This is very helpful too for folks like me who are likely to get a migraine if we don’t snack between meals, even if the meal was super-healthy, low GI etc. Thanks, Dr B.
Does this include peanuts. In the Paleo literature they say that peanuts are not actually nuts but legumes. However, I find they work really well for quenching my appetite. What do you think? By the way, thanks for this wonderful site and the excellent science you provide.
Dr Briffa,
I have been following your blog for some time now, and despite finding it difficult sticking entirely to a low carb approach, due to a history of eating disorders, I have tried to maintain some consistency, i.e not going over board on carbohydrate intake. I was curious to find recently a blog, by a ‘nutritional researcher’ (I don’t have much idea of his clinical/medical background, if any!) Matt Stone, @ 180 degree health, whom advocates a ‘high everything diet’ to combat metabolic problems. He claims that eating with such an approach though going against todays conventional wisdom, of eating low carb, would have a beneficial effect on leptin, which he says should be the focus for health, rather than insulin. In turn, explaining that low carb diets, and dieting in general result in adrenal fatigue, and so are detrimental to the overall health of the body and mind. He goes on to argue that, insulin is a red herring, and to look at the variety of cultures whom have optimal health despite having high carbohydrate intake, like wise saturated fat etc, saying that the real problems have arisen due to fructose intake, omega 6, and sugar generally. Though I was dubious at first, he provides a wealth of scientific studies and practitioners to support his claims and they seem somewhat credible deductions. I would be very interested to know what your take is on this perspective with regards to the low carb approach because I wonder whether adrenal fatigue resulted in my eating disorder which began with a year of low carb/atkins dieting. I would be very grateful for any response as I am trying as best I can to overcome the problems that I currently face. Thanks!
C’mon John. Eat more, lose weight. That’s what the paper shows. I like your blog and appreciate your putting common sense ahead of dogma so I figure you had a bad day. This just can’t be right. When you go and look at the original paper, you can see just how bad it is; AJCN will, of course, publish any crap if it comes from made men. First off, it conforms to standards of medical nutritional paper: no figures. Only mind-numbing tables with endless statistics. Also, data is broken into groups (quartiles). This is so common nobody asks why we keep doing it. We keep doing it because we have a lot of data and we would need a big computer to do a simple plot of one variable against the other. At least that was the idea fifty years ago. Nutritionists have yet to figure out that you can use computers for something besides canned statistics. Anyway, let’s go to Table 2. Energy increases as number of snacks or per cent energy from snacks increases. Huh? You eat more but you get thinner. If you tried to show this for low carbohydrate diets, you would never get it published or if you did, some MD who took Physics 101 thirty years ago would tell you it violates the laws of thermodynamics. I thought I read it wrong but no. The authors admit it right up front and… there’s precedent. What follows is a masterpiece of double-talk. “An inverse association between snacking and weight was also shown by other authors, despite the increased energy intake associated with snacking (14, 33). Snacking was shown to be associated with improved diet quality (12, 17, 33) and increased intakes of fruit, whole grains, and fiber (12, 17), which could promote satiety and reduce risks for obesity.” So if you eat the right stuff, calories don’t count. This is the cuckoo land of medical nutrition, you know, brown rice will cure your diabetes or is it prevention. Well, we all have a bad day now and then but, c’mon John, this is not about anything.
Richard
Regarding the apparent finding of higher caloric intakes being associated with lower body weight, you’ll see that I did add two caveats. “It is possible, say, that individuals of healthy weight quite naturally feel less need to restrict their food intake and are more relaxed about eating snacks. Also, overweight individuals may tend to under-report any snacking they partake in.”
Are you happy with these caveats?
But now let’s take these ‘eat more/weight less’ findings at face value for a moment. Is it possible to eat more and weigh less? Well, while I know how much doctors, dieticians and scientists are wedded to the calorie principle, my belief it is a gross oversimplification of the impact of eating of body weight.
It is possible, is it not, that the form that the calories one consumes take may have an impact on body weight? Could, for example, an emphasis on relatively low-carbohydrate foods have merit here, through an insulin-lowering effect and/or other metabolic effects? Might certain macronutrient make-ups (e.g. a higher protein have a ‘metabolic advantage’ over others? Theoretically, at least?
And we know that restricting calories can suppress metabolism. Could the reverse be true? Could eating more actually help stimulate the metabolism and allow individuals to eat more and still maintain a relatively low body weight? I’m not aware of any definitive science on this, but are you open to the possibility?
References 1 and 2 above show that increased food intake frequency is associated with lower levels of insulin. The first shows lower levels of cortisol too. It would seem reasonable to suggest that these benefits might mitigate the effects of eating more, no?
As I pointed out in the piece, snacking is generally frowned upon. However, I have in practice found healthy snacking to be generally very helpful for individuals wishing to lose excess fat. By combating undue hunger, it helps individuals make healthy food choices easier. And it makes healthy eating more sustainable too. Not everyone needs to snack healthily between meals to lose fat successfully, but for many it seems to be a real boon.
The AJCN study is, as you know, epidemiological in nature, and therefore quite limited in its ability to tell us anything, to be frank. Studies of this nature are prone to confounding, but this was already acknowledged in the piece. But I did want to use it at least as a point of interest to discuss the potential merits of snacking.
And if it turns out that some people really can eat more and be lighter than other people, I won’t be in the least bit surprised, when one considers the impact that dietary make-up, eating frequency and variance in metabolic rate might have regarding the effect food has on body weight.