Q: Is it better to have skim/low-fat milk or whole milk?

A: This is such a great question and one that is getting more and more media attention.
Dairy does not agree with everyone (lactose, whey or casein sensitivities are common) but for those of you who enjoy a serving or two of dairy every day, what should you be choosing? We’ve heard for so long that cutting fat from dairy products is the way to a slimmer waistline and better overall health but is this necessarily the truth? We’ve also heard that the saturated fat in dairy products is going to clog our arteries and lead to the development of heart disease. Regardless of what we've heard, at this point in time the evidence suggests that saturated fat has a neutral effect on heart health.

Research is continuing to emerge regarding the importance of consuming full-fat dairy products over its non-fat counterparts.

First let’s look at the facts from recent studies (I won’t bore you with the details – we’ll just summarize):

• A study published in the Scandinavian Journal of Primary Health Care reports that adult men who consumed high-fat dairy products were significantly less likely to develop central obesity (arguably the type of obesity with the highest negative impact on our health) over a 12 year period compared to men who did not or rarely ate high-fat dairy products. 
• A meta-analysis of 16 observational studies published in the European Journal of Nutrition suggests that an inverse relationship exists between consumption of high-fat dairy and obesity risk (meaning the higher the intake of high-fat dairy, the lower the obesity risk). 
• A study published in the Archives of Diseases in Childhood suggested that consumption of low-fat milk is associated with increased weight gain over time.
• A study conducted at the Harvard School of Public Health found that there was an 85 percent increase in infertility rates in women who consumed two or more servings of low-fat dairy in comparison to women who consumed one or less than one serving of low-fat dairy per week. 

So how can this be? If it’s the equation of calories in versus calories out that dictates our weight, shouldn’t we cut the calories from dairy products by reducing the amount of fat in the product (fat contains 9 calories per gram, so reducing fat from a food can reduce its calories significantly)? If you remember from my post last week, calorie counting is not always the solution.

At this point there is not a definite reason as to why this link between high-fat dairy consumption and reduced risk of obesity exists – some researchers hypothesize that it is the satiety factor of fat (meaning it helps to keep us fuller longer) and therefore we don’t feel the need to consume an excessive amount of food. Another hypothesis relates to the effect the fatty acids in dairy products have on our hormones and gene expression, which alters the amount of energy our bodies burn and store. 

More Sugar?

We often hear recommendations to go with a full-fat variety over a fat-free variety due to the sugar that can be added to low-fat products to make them more palatable, however this is not the case with milk or cheese. Both the full-fat and low-fat products contain the same number of grams of sugar per serving. The only true difference between the two is the fat content. Contrary, if we were to compare full-fat versus low-fat ice cream, we would likely see a difference in the sugar content per serving, with the low-fat version containing more grams of sugar per serving than the full-fat variety. Always be sure to take a look at the nutrition facts panel and the ingredient list when determining how much added sugar a product contains. 

Questioning the Research

I want to touch on one important point before we finish our discussion today. I want you to keep in mind that the research studies conducted on high-fat dairy products and obesity or weight gain are observational studies rather than randomized controlled trials (the gold standard). This means that we are unable to say that low-fat dairy consumption causes weight gain or that high-fat dairy consumption prevents weight gain. From this research we can only conclude that consumption of high-fat dairy is associated with reduced risk of obesity or weight gain. Although researchers do their best to remove all other variables that may impact this relationship, we are still unable to conclude a cause/effect relationship between the high-fat dairy and obesity risk.

Recommendations: If dairy products agree with you I recommend going with the full-fat variety and simply watching the number of servings you consume in a day. 

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Yours in Health,

Kristin