Protein-supplemented diet found to be more effective than carb-supplemented one for maintenance of weight loss

Of the many different dietary strategies that can be used to lose weight, I favour a relatively low-carbohydrate, protein-rich diet. Some of the rationale about the low-carb element of such a regime is that carbohydrate (say from sugary and starchy foods) is the dietary element that most disrupts blood sugar, which tends to knock on to elevated levels of insulin ” the chief ‘fat storage’ hormone in the body. And at least some of the rationale for a relatively protein-rich diet comes from the fact that, generally speaking, this dietary element sates the appetite more than either fat or carbohydrate.

So, in short, what we have with a relatively protein rich and low-carb diet is one which tends to be effective at satisfying the appetite and, at the same time, tends not to promote fat deposition in the body. It’s no wonder then that I find it is this very sort of diet that leads to lasting and satisfying weight loss in those who adopt this way of eating in the long term. And it’s perhaps no wonder that these types of diet generally outperform carbohydrate-rich ones in the weight loss stakes. For example, back in November I reported on a study which found that individuals adopting a lower carb, higher protein diet shed more fat than those on a diet higher in carb and lower in protein.

Earlier this week saw the electronic publication of a study which pitted a protein-rich and carb-rich diet against each other [1]. 48 obese individuals started this study by adopting a very low calorie diet for 5-6 weeks to induce weight loss. After this, though, individuals were instructed to eat a low fat diet. Some of the individuals supplemented their diet with carbohydrate (in the form of maltodextrin), while others supplemented their diet with protein (50 g of casein or whey protein each day). Individuals could eat as much of their new diet as they liked for a period of 12 weeks, at which point they were assessed in terms of weight and various biochemical measurements.

At the end of the study, compared to the carb-supplemented individuals, those supplemented with protein lost an average of 2.3 kg (5 lbs) more. Crucially, this improved weight loss was almost entirely from fat.

Triglyceride levels increased more in the higher-carb eaters (not a good thing). On the other hand, blood glucose levels increased more in the protein supplemented group. Despite this, though, HBA1c levels (which give a measure of blood sugar control over the preceding 3 months) did not differ between the two groups.

The authors of this study concluded that: These results show that low-fat, high-casein or whey protein weight maintenance diets are more effective for weight control than low-fat, HC diets and do not adversely affect metabolic and cardiovascular risk factors in weight-reduced moderately obese subjects without metabolic or cardiovascular complications.

References:

1. Claessens M, et al. The effect of a low-fat, high-protein or high-carbohydrate ad libitum diet on weight loss maintenance and metabolic risk factors. Int J Obes (Lond). 20 Jan 2009 [Epub ahead of print]

One Response to Protein-supplemented diet found to be more effective than carb-supplemented one for maintenance of weight loss

  1. Nigeepoo 1 February 2009 at 10:58 pm #

    Just a minor quibble with the above article:
    “insulin” the chief ‘fat storage’ hormone in the body”.

    Insulin is the glucose & amino acid-storage, stop fat-burning hormone. Acylation Stimulating Protein is the fat-storage hormone. See Metabolic response of Acylation Stimulating Protein to an oral fat load.

    If insulin was a fat-storage hormone, serum insulin would rise with an oral fat load. It doesn’t, but serum ASP does.

    Q.E.D.

Leave a Reply