Why the Proposed 'Star' Ratings for Food are a Terrible Idea..

By Cliff Harvey ND

A recent article in the New Zealand Herald: 'Choice! Food goodness at a glance' tells of the proposed (soon to be implemented) Government initiative to label foods according to a 'star rating', similar to that used to show energy efficiency in appliances. In this system a rating of anywhere between half and five stars will be given according to how (supposedly) 'healthy' a food is. 

Source: New Zealand Herald http://media.nzherald.co.nz/webcontent/infographics/357/graphicyog.jpg

Apparently this initiative aims to help shoppers identify which foods are healthiest. 
Unfortunately the system is fundamentally flawed and many healthy foods will be given terrible ratings, whilst other foods responsible for much of our modern preponderance of metabolic disorders will be given favourable ratings. 
While I applaud the efforts to make choosing healthier foods easier for consumers this latest initiative is incomplete at best, and counter-productive at worst. 

According to the National Party website the food rating system "takes into account four aspects of a food associated with increasing the risk factors for chronic diseases (energy, saturated fat, sodium and total sugars)"

Challenges arising from this rating system include:

Energy is a poor indicator of food quality

Total calorie intake may not be a reliable indicator of food quality, nor of health outcomes. 
According to Feinman and Fine (2004) the idea that a 'calorie is a calorie' defies the second law of thermodynamics and is not congruent with the vast array of metabolic reactions and interactions within the human, or any other organism. Calorie intake may well be self-limited when appropriate food choices are made (those choices that encourage a metabolically 'well-ordered' system.) This has been demonstrated by research showing the superiority of ad-libitum (eat as much as you like) higher-fat, lower-carbohydrate diets over the standard 'best-practice' diet which is high in carbohydrates, low in fat and restricted in calories  (Bueno, de Melo, de Oliveira, & da Rocha Ataide, 2013; Sondike, Copperman, & Jacobson, 2003; Volek, Quann, & Forsythe, 2010; Yancy, Olsen, Guyton, Bakst, & Westman, 2004)
This also plays into the flawed ideology that fat is 'bad' because it is more calorie dense than the other macronutrients. By this rationale there would be a more favourable rating applied to foods that are high in refined carbohydrates as compared to healthy fats such as butter, ghee and coconut oil which contain more than twice the calorie quotient per gram. 


Saturated fats aren't bad for us!

Saturated fats are a veritable whipping boy in the government associated aspects of the nutrition and dietetic industries. Despite demonstrable proof that saturated fats are not the villains they have been made out to be, there is still a lingering bias against them which can be very counterproductive to effective nutrition labeling and education. 
Schofield and colleagues (2014) from AUT's Human Potential Centre, Auckland University and Holistic Performance Nutrition evaluated the evidence for reducing fat and saturated fat intake in respect to public health outcomes and noted: "the paucity of statistical evidence linking either reduced fat or modified fat (including saturated fat) with disease end-points" and that both a 2011 Cochrane review (Hooper et al., 2011) and other meta-analyses  find little statistical evidence linking saturated fat intake with cardiovascular mortality. 
There is little if any compelling evidence that reducing fat or saturated fat has any appreciable benefit to health, and in fact there may be compelling benefits derived from the consumption of several saturated fat types within a normal, healthy (natural, whole and unprocessed) diet.
For example under these regulations it could be assumed that a high polyunsaturated fat  oil (such as sunflower oil) or a monounsaturated fat oil such as olive oil would score more highly than coconut oil (which  predominantly consists of saturated fatty acids). Saturated fats include the medium chain triglycerides (capric, caprylic, caproic and lauric acids) which have been demonstrated to increase metabolic rate more than long chain triglycerides (Seaton, Welle, Warenko, & Campbell, 1986), suppress fat deposition through enhanced thermogenesis and fat oxidation, and may help to preserve insulin sensitivity in animal models and patients with type 2 diabetes (Nagao & Yanagita, 2010). When compared to the supposedly 'healthier' fats they may promote greater weight-loss, fat-loss and overall fat oxidation (St-Onge & Bosarge, 2008; St-Onge, 2012). These MCTs (which are saturated fats) "may be considered as agents that aid in the prevention of obesity or potentially stimulate weight loss.”(St-Onge, Ross, Parsons, & Jones, 2003).
So tell me why they would have a poor rating?


Sodium content is a poor indicator of food quality

Diets that are extremely high in processed and refined foods may be too high in sodium, however contrary to popular belief the average intake of sodium in New Zealand (which has been estimated at 3900mg per day according to McLean, Williams, Mann, & Parnell (2012)) is well within the range indicated as having no effect on health or mortality. The range within which no discernible health effects are seen lies somewhere between 2,645 and 4,945 mg (Graudal et al., 2014) or as high as 6000mg (Alderman & Cohen, 2012), and so the recommendation to reduce sodium intake is confusing, unnecessary and a poor rating scale for the quality of a food item. How for example would kelp, or a natural rock or celtic salt fare on this new scale?


Total sugars...but what about highly processed and refined carbs?
Highlighting the importance of regulating sugar intake is very important and to be applauded. But there appears to be a gaping hole within this rating system and that is the lack of appreciation for the negative effects of a diet that is too high in highly processed and refined non-sugar carbohydrates. I can only assume that the industry pressure to continue to promote 'whole-grains' and other potential blood glucose bombs has limited the carbohydrate focus to sugar. 
Carbs certainly aren't the enemy, but highly processed and refined carbohydrates are certainly not appropriate for most people, most of the time, and so a greater attention should be paid to these within dietary guidelines and any proposed food labeling systems. 


Conclusion
Maybe it's a start, but this rating system is incomplete and won't help to better educate consumers, nor encourage the best outcomes. Many healthy foods will be rejected by consumers due to flawed rationale, and many unhealthy foods will be prioritised instead. 

References:



Alderman, M. H., & Cohen, H. W. (2012). Dietary Sodium Intake and Cardiovascular Mortality: Controversy Resolved?American Journal of Hypertension, 25(7), 727-734. doi: http://dx.doi.org/10.1038/ajh.2012.52 

Courchesne-Loyer, A., Fortier, M., Tremblay-Mercier, J., Chouinard-Watkins, R., Roy, M., Nugent, S., . . . Cunnane, S. C. (2013). Stimulation of mild, sustained ketonemia by medium-chain triacylglycerols in healthy humans: Estimated potential contribution to brain energy metabolism. Nutrition, 29(4), 635-640. doi: http://dx.doi.org/10.1016/j.nut.2012.09.009

Feinman, R. D., & Fine, E. J. (2004). A calorie is a calorie" violates the second law of thermodynamics. Nutr J, 3(9).

Graudal, N., Hubeck-Graudal, T., & Jurgens, G. (2011). Effects of low sodium diet versus high sodium diet on blood pressure, renin, aldosterone, catecholamines, cholesterol, and triglyceride. Cochrane Database of Systematic Reviews, 11. 

Graudal, N., Jürgens, G., Baslund, B., & Alderman, M. H. (2014). Compared With Usual Sodium Intake, Low- and Excessive-Sodium Diets Are Associated With Increased Mortality: A Meta-Analysis. American Journal of Hypertension. doi: 10.1093/ajh/hpu028

Han, J. R., Deng, B., Sun, J., Chen, C. G., Corkey, B. E., Kirkland, J. L., . . . Guo, W. (2007). Effects of dietary medium-chain triglyceride on weight loss and insulin sensitivity in a group of moderately overweight free-living type 2 diabetic Chinese subjects. Metabolism, 56(7), 985-991. doi: http://dx.doi.org/10.1016/j.metabol.2007.03.005

Institute of Medicine of the National Academies. (2005). Dietary reference intakes for water, potassium, sodium, chloride and sulphate. Washington, D.C.

Institute of Medicine of the National Academies. (2013). Sodium intake in populations: Assessment of evidence. Washington, D.C.


McLean, R., Williams, S., Mann, J., & Parnell, W. (2012). 1051 Estimates of New Zealand Population Sodium Intake: Use of Spot Urine in the 2008/09 Adult Nutrition Survey. Journal of Hypertension, 30, e306 310.1097/1001.hjh.0000420510.0000493854.ca. 

Nagao, K., & Yanagita, T. (2010). Medium-chain fatty acids: Functional lipids for the prevention and treatment of the metabolic syndrome. Pharmacological Research, 61(3), 208-212. doi: http://dx.doi.org/10.1016/j.phrs.2009.11.007

Seaton, T. B., Welle, S. L., Warenko, M. K., & Campbell, R. G. (1986). Thermic effect of medium-chain and long-chain triglycerides in man. The American journal of clinical nutrition, 44(5), 630-634. 

St-Onge, M.-P., & Bosarge, A. (2008). Weight-loss diet that includes consumption of medium-chain triacylglycerol oil leads to a greater rate of weight and fat mass loss than does olive oil. The American journal of clinical nutrition, 87(3), 621-626. 

St-Onge, M.-P., Ross, R., Parsons, W. D., & Jones, P. J. H. (2003). Medium-Chain Triglycerides Increase Energy Expenditure and Decrease Adiposity in Overweight Men. Obesity Research, 11(3), 395-402. doi: 10.1038/oby.2003.53

Taylor, R. S., Ashton, K. E., Moxham, T., Hooper, L., & Ebrahim, S. (2011). Reduced Dietary Salt for the Prevention of Cardiovascular Disease: A Meta-Analysis of Randomized Controlled Trials (Cochrane Review). American Journal of Hypertension, 24(8), 843-853. doi: 10.1038/ajh.2011.115

Thomson, B. M., Vannoort, R. W., & Haslemore, R. M. (2008). Dietary exposure and trends of exposure to nutrient elements iodine, iron, selenium and sodium from the 2003–4 New Zealand Total Diet Survey. British Journal of Nutrition, 99(03), 614-625. 

Thomson, C. D. (2004). Selenium and iodine intakes and status in New Zealand and Australia. British Journal of Nutrition, 91(05), 661-672.