I saw this quote in a Psychology today article recently “If all you have is a hammer, everything looks like a nail.” (The right tool for the job). It’s not new of course, it’s one we’ve heard often. But as I reflect over my varied careers and life experiences, I realise how often I’ve fallen into the “hammer trap”, where a particular experience colours my world view profoundly.
It goes like this: Something I’ve tried – whether it be a diet (Zone, Paleo, low carb, raw vegan …, name yours) or some self improvement course, religion, inspirational book, peak experience, adventure, therapy, medication, sport, exercise.. you get the picture. This thing you experience – it changes your life in some way, in fact it makes it profound difference. Every issue / health problem you see others having – your recent discovery appears to you be the answer.
As a group of paleo nutrition, and often low carb advocates – we tend to view the world’s health / weight problems as though paleo / low carb is the answer to everything. E.g. low carb will fix everyone who is overweight, it’s even good for athletes once they get used to burning fat instead of carbs…
I’m not saying it isn’t, I’ve seen incredible results in many people, however – I’m also aware of how science changes and evolves. And how little we really know, and how varied humans are. [Edit: To date I haven't seen any evidence against a 'paleo' paradigm being the best dietary advice - by this I mean removing grains, especially gluten grains, chemically extracted vegetable oil and other nasty fats like trans fats, processed food, multiple synthetic additives and sugars - especially fructose. This is what I recommend across the board. See comments] I cringe when I think how I’ve had my own past “hammer” of one sort or another and sought to fix everyone’s problems with it. So when we have only one answer to a problem, then we hear it’s not working e.g. ‘low carb’ isn’t working for some-one, we think “they’re not doing it right” or some version of that. Or perhaps we hear that someone added in more carbs and their weight loss increased and their health improved. If it doesn’t fit for us – we then ignore it or try to rationalise it somehow.
Take my Zone days for example – I thought all anyone needed to do was go on the Zone diet and their problem would be solved. Very low carb was incorrect – the body is forced to release cortisol for gluconeogenesis (not good). High carb was also wrong as it caused excess blood glucose and consequent insulin release, and then fat storage and hunger. I got stuck for a while in my view that the Zone was the only way to go.
At University I was given this review article:
Division of Endocrinology, Diabetes and Metabolism, Tufts-New England Medical Center, Boston, Massachusetts 02111, USA. firstname.lastname@example.org
There is considerable uncertainty over whether any one dietary pattern broadly facilitates weight loss or maintenance of weight loss, and current dietary guidelines recommend a spectrum of dietary composition for the general population. However, emerging evidence suggests that specific dietary compositions may work better for identifiable groups of overweight/obese individuals based on their individual metabolic status. In particular, characteristics of insulin dynamics, such as insulin sensitivity or insulin secretion status, may interact with diets that vary in macronutrient composition to influence the weight loss achieved with a hypocaloric diet.
If you do have access to the full article – it has a useful discussion on the complexities of insulin secretion, insulin sensitivity, insulin resistance, fasting insulin vs post prandial insulin… (I.e. there is more to the picture than high carbs = high insulin = fat gain)
One studies it referred to was this one:
Department of Medicine, University of Colorado Health Sciences Center, Denver, CO, USA.
To determine whether macronutrient composition of a hypocaloric diet can enhance its effectiveness and whether insulin sensitivity (Si) affects the response to hypocaloric diets.
RESEARCH METHODS AND PROCEDURES:
Obese nondiabetic insulin-sensitive (fasting insulin < 10 microU/mL; n = 12) and obese nondiabetic insulin-resistant (fasting insulin > 15 microU/mL; n = 9) women (23 to 53 years old) were randomized to either a high carbohydrate (CHO) (HC)/low fat (LF) (60% CHO, 20% fat) or low CHO (LC)/high fat (HF) (40% CHO, 40% fat) hypocaloric diet. Primary outcome measures after a 16-week dietary intervention were: changes in body weight (BW), Si, resting metabolic rate, and fasting lipids.
Insulin-sensitive women on the HC/LF diet lost 13.5 +/- 1.2% (p < 0.001) of their initial BW, whereas those on the LC/HF diet lost 6.8 +/- 1.2% (p < 0.001; p < 0.002 between the groups). In contrast, among the insulin-resistant women, those on the LC/HF diet lost 13.4 +/- 1.3% (p < 0.001) of their initial BW as compared with 8.5 +/- 1.4% (p < 0.001) lost by those on the HC/LF diet (p < 0.04 between two groups). These differences could not be explained by changes in resting metabolic rate, activity, or intake. Overall, changes in Si were associated with the degree of weight loss (r = -0.57, p < 0.05).
The state of Si determines the effectiveness of macronutrient composition of hypocaloric diets in obese women. For maximal benefit, the macronutrient composition of a hypocaloric diet may need to be adjusted to correspond to the state of Si.
[NOTE: An important point to note is that any diet that is calorie reduced is likely to reduce carbohydrate calories from previous intake, so don't make the assumption the these women increased their carbohydrate intake from their pre-diet one. The calorie reduction was 30% - so carbs could potentially be 30% less than previous intake]
I have to say at the time I was SO entrenched in low/moderate carb i.e. Zone diet was “THE RIGHT WAY TO EAT” I actually couldn’t get my head around the fact that this study showed that when two different calorie reduced diets were tested some women lost more weight on the higher carb diet. Significantly more than they did on a higher protein, lower carb diet.
My point? Let’s not assume that our “hammer” i.e. what has worked for us is the best answer for everyone else. Their body may run very differently from our own, and a like this study shows may run better on a very different mix of fuel.
Be aware that what has worked for you has highly coloured your world view. Try and put it aside, and you might discover that what the other person needs a screwdriver. Or when they say they are losing weight eating more carbs rather than less, they are not deluding themselves.
More reading: Lyle MacDonald discusses insulin sensitivity and fat loss in this 2008 article: Insulin Sensitivity and fat loss.