Nutrient Profiling Systems and health?
Date Published11 December 2012
By Helen Mair, Dairy Australia
© Lawmedia Pty Ltd, December 2012 -January 2013
This article by our guest columnist Helen Mair, Health & Nutrition Policy Advisor to Dairy Australia challenges some of the assumptions behind nutrient profiling systems, such as the Nutrient Profile Scoring Criteria in the latest Health Claims Standard. It also reveals inconsistency in levels of scientific evidence necessary for different Health Claims.
Nutrient Profiling Systems (NPS) have been developed to help consumers choose healthy foods either by preventing ‘unhealthy’ foods making claims implying they are ‘healthy’ foods or to categorise foods into ‘healthy’ and not so healthy. Examples of this include the proposed Health Claims Standard Nutrient Profile Scoring Criteria (NPSC), Front of Pack Labelling, School Canteen Guidelines, and Health Facility Guidelines.
These systems generally focus on energy, nutrients to avoid (saturated fat, sodium, and sugar) and increasing consumption of fruits and vegetables, sometimes fibre, and occasionally calcium as an under consumed nutrient.
The proposed FSANZ Health Claims Standard NPSC calculates for: energy, nutrients to avoid (saturated fat, sodium, and sugar) and foods/nutrients to increase or of benefit (protein, calcium, fibre, fruits, vegetables, nuts and legumes) for specified categories of foods.
To make a ‘Health Claim’ on a product under the proposed standard, the product must comply with all requirements of the Food Standards Code including other aspects of the Health Claims Standard and the NPSC. The choice is either a ‘Preapproved’ (High Level & General Level) or a ‘Self substantiated’ (General Level only) Health Claim. The proposed standard considers the level of scientific evidence required to substantiate a ‘Health Claim” to be the highest level possible or what is known as ‘convincing.’ Similarly it would be expected that the evidence underpinning a NPS such as the NPSC would also substantiate the health relationship with the NPS approach to be comparatively up to date and evidence based.
The approach to evidence reviews regarding food intake and health outcomes has shifted focus from individual nutrients and health relationships to foods or diets and health relationships. This makes sense; consumers eat foods and diets, not nutrients in isolation. This is evidenced by the most recent Dietary Guidelines Reviews in both the US and Australia, literature reviews considered foods and health outcomes relationships to underpin Dietary Guidelines. Previously food groups were defined primarily on key nutrients provided.
But how do the two approaches compare in the current literature, and risk management strategies regarding relationships with health outcomes?
Firstly let’s look at a ‘nutrients to avoid’ or ‘nutrients in isolation’ approach.
In 2010 the FAO Fats and fatty acids in human nutrition report of an expert consultation advised that replacing Saturated Fatty Acids (SFA), with Poly Unsaturated Fatty Acids (PUFA) was beneficial for lowering total and LDL cholesterol. There was no evidence to support replacement with refined carbohydrate. There was insufficient evidence to support replacement with Mono Unsaturated Fatty Acids (MUFA). In the interim years the most recent evidence has now found that the benefit of replacement of SFA for reduced risk of Coronary Heart Disease (CHD) with PUFA is limited to n-3, not, n-6. Replacement with refined carbohydrate increases risk, and there is no association with benefit for replacement with MUFA. This is important, because when something from a food or a diet is removed; it is generally replaced with something – clearly, what SFA is replaced with matters. What also must be considered, is, according to an IOM report LDL cholesterol is no longer considered a useful marker for CVD risk.
If we look at the evidence regarding sugar, the association is with dental health issues except for sugar sweetened beverages. However sugar is a refined carbohydrate, which from the SFA evidence and other evidence looking at specific health effects is associated with metabolic and cardiovascular health issues. So limiting sugar may have some benefit, but the overall issue with refined carbohydrate is not addressed.
When considering sodium and blood pressure, evidence points to the relationship with other nutrients such as Chloride (increased risk) Potassium, Magnesium, Calcium and in dairy, peptides (reduced risk) as being important.
When aiming to reduce the risk of diet related non-communicable diseases, obesity is a major risk factor. If we consider the evidence regarding macro nutrients in a kilo joule controlled diet, there is no relationship to obesity, rather energy is key. If we consider unrestricted diets, evidence indicates that macronutrients such as protein, fat, low Glycaemic Index, and complex carbohydrates play a role in satiety, likely along with other micronutrients (e.g. phyto, minerals). Evidence also suggests in an unrestricted diet, consumers that follow dietary advice to reduce fat or saturated fat, do not reduce overall energy intake but rather substitute kilojoules from other sources and may also reduce dairy food intake.
Further issues arise through considering nutrients in a homogenous fashion; for example there are over 400 fatty acids in milk fat, of those that are saturated, not all have the same effect on the body. Similar considerations must be made for other fats, carbohydrates, and proteins.
For example the researcher Arne Astrup commented in his 2011 paper which considered the evidence regarding saturated fat and the prevention of cardiovascular disease: “The effect of particular foods on CHD cannot be predicted solely by their content of total SFAs because individual SFAs may have different cardiovascular effects and major SFA food sources contain other constituents that could influence CHD risk”
Let’s now consider a ‘foods’ based approach.
The most recent NHMRC Dietary Guidelines Literature review resulted in evidence statements for each of the ‘Core’ food groups.
Traditionally ‘core’ dairy foods were considered primarily for the contribution of calcium to the diet. However when considering the NHMRC evidence regarding the association of the food with health outcomes, of the 12 ‘Core’ (milk, cheese, yoghurt, and custard) dairy foods statements, 11 applied to both regular and reduced fat, 10 were associated with a reduced risk of adverse health outcomes relating to cardiovascular health (4), metabolic health (2), cancers (3) and bone health (1). The two considering weight found no association. 4 statements were level B and 8 were level C according to NHMRC evidence grading.
Compare this with the evidence statements for vegetables: of the 8 ‘Core’ vegetable foods statements, 3 applied to all vegetables and 5 applied to specific vegetables, 6 were associated with reduced risk of adverse health outcomes (4 to cancers and 2 to cardiovascular health). 1 for preserved vegetables was associated with increased risk of a type of cancer, and 1 statement was associated with reduced risk of weight gain. 2 statements were level B evidence and 6 statements were level C.
We also need to consider, for health, the ability to identify nutrient rich foods (the ‘core’ foods) is important. Nutrient rich ‘core’ foods provide increased nutrients in proportion to energy and budget. Encouraging a diet based around nutrient rich ‘core’ foods discourages consumption of nutrient poor energy dense foods. Consumers are more likely to apply this approach if consuming enough ‘core’ foods is encouraged. This is particularly important for those ‘core’ foods that are significantly under consumed in the Australia population such as dairy foods and vegetables.
If you look at the evidence regarding the associations between foods (the complete food matrix) and health outcomes vs. that regarding nutrients in isolation, any risk management strategy must consider the benefits of getting ‘enough’ of a food associated with a reduced risk of adverse health outcomes rather than discouraging consumption by implying that somehow the food is unhealthy just because the food contains a ‘nutrient to avoid’.
Any healthy diet promoting strategy including Nutrient Profiling Systems, should promote all ‘nutrient rich core foods” associated with reduced rates of non-communicable diseases. This requires simple consistent consumer messages. Perhaps that message should be ‘ base your diet around nutrient rich ‘core’ foods’ and be clear what those nutrient rich ‘core’ foods are, and how much is enough. This is a message, the evidence supports, and a message that would cement a national nutrition policy framework.
For a full bibliography for this article, please see the following Dairy Australia webpage.
Health & Nutrition Policy Advisor Dairy Australia
03 9694 3703 I 0458 037 123 I firstname.lastname@example.org