Changing the View on Fat

By: Eliza Short, AgropurIngredients Dietetic Intern

The debate on whether to choose full-fat or low-fat dairy products has led researchers to conduct countless studies covering environmental, societal, nutrition and health perspectives. The following discussion will be limited to cardiovascular health considerations. Heart disease is the leading cause of death in the United States. Researchers are working to identify which dietary components contribute to heart disease, and what can help prevent it.

The 2010 Dietary Guidelines for Americans recommend that we decrease our intake of solid fats in our diets, also known as saturated and trans fats.1 The major sources of saturated fats include full-fat cheese, pizza, grain-based desserts (donuts, cookies, etc), dairy-based desserts, chicken and chicken mixed dishes, sausage, franks, bacon, and ribs. We are told to instead replace them with the liquid monounsaturated and polyunsaturated fats. These healthy fats have been shown to lower total and LDLblood cholesterol levels, while saturated fats have been shown to increase levels of LDL cholesterol. As LDL travels through our blood, it deposits cholesterol in arteries, leading to plaques and narrowing of the blood vessels. This is what can ultimately cause cardiovascular disease. On the other hand, the unsaturated fats do not contribute to this plaque formation. Due to the negative effects of saturated fats, low-fat or fat-free dairy has been the recommendation for years. However, there are many points to be considered when deciding whether to consume full-fat or low-fat dairy products.

The Facts

Low-fat and fat-free foods

In general, lower fat foods contain a higher proportion of carbohydrate, often in the form of added sugar. When people switch from full-fat foods to lower-fat options, they tend to substitute lost calories from fat with carbohydrates instead. This is evident in recent consumer trends for “low-fat frozen yogurt” which contains much less fat, but is very high in sugar. With the perception that these low-fat products are healthier, consumers may tend to overindulge on the high-sugar options. While this is true in some cases, fat-free milk contains all of the same nutritional benefits of the full-fat version, simply without the saturated fat content. In a recent study, most foods that were positively associated with weight gain were starches or refined carbohydrates; no significant differences were seen for low-fat and skim milk versus whole-fat milk.2

  • Bottom Line: If you prefer to consume higher-fat dairy products, you may benefit from lowering saturated fat intake from other foods, such as sweets that do not contain the same healthful nutrients as milk.

Fullness

The higher fat dairy options allow people to feel more full and satisfied after consuming. If one does not feel full after drinking a glass of skim milk, he or she may reach for a second or third, which increases overall calories and does not give one the same satiety as a higher-fat option.

  • Bottom Line: Pay attention to what works best for you

Other saturated fat sources

Dairy products are only one source of saturated fats, and often have health components as well, such as protein, vitamins, and minerals that are essential to one’s diet. When comparing dairy to other sources of saturated fats such as processed and red meats, although these are good sources of protein and iron, when consumed on a daily basis they have been shown to increase the risk of cardiovascular disease and some cancers.3-5

  • Bottom Line: If you are going to eat foods that contain saturated fats, choose foods that have some nutritional benefits as well, such as milk, and eat other sources in moderation.

Blood sugar control

Studies have shown that people who had 8 or more portions of high-fat dairy per day had 23% lower risk of type 2 diabetes.6 Fat and protein are known to helps delay digestion and absorption of food into the blood stream. This helps keep blood sugars stable. However, this does not mean that adding high-fat dairy to your diet will help protect against type 2 diabetes. Consumption of high-fat dairy products can be a part of a healthy diet, but it is still important to be aware of how much you consume, since they can be high in calories which can contribute to becoming overweight and therefore increase risk for diabetes.

  • Bottom Line: Fat and protein in milk help to delay absorption of food into the blood, to keep blood sugars in better control if one is at risk for type 2 diabetes.

Weight loss

In weight loss trials, those who consumed higher-fat products had significantly greater weight loss than those who consumed a lower-fat diet.7 This could be due to the satiety effect of fat, which may help one eat fewer calories overall.

  • Bottom Line: Eating higher-fat foods may help you to eat less often since it allows one to feel full for a longer period of time.

References

  1. U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2010. 7th Edition, Washington, DC: U.S. Government Printing Office, December 2010.
  2. Mozaffarian D, Hao T, Rimm EB, et al. Changes in diet and lifestyle and long-term weight gain in women and men. N Engl J Med. 2011; 364:2392-2404.
  3. Big Fat Myths: Why advice to cut meat and dairy is under attack. Nutrition Action Health Letter. 2015; 42(10):3-6.
  4. Sinha R, Cross AJ, Graubard BI, Leitzmann MF, Schatzkin A. Meat intake and mortality: a prospective study of over half a million people. Arch Intern Med. 2009; 169:562-71.
  5. Otto M, Mozaffarian D, Kromhout D, et al. Dietary intake of saturated fat by food source and incident cardiovascular disease: the multi-ethnic study of atherosclerosis. Am J Clin Nutr. 2012; 96:397-404.
  6. Broyd, N. High-Fat Dairy May Lower Diabetes Risk. 2014. Web. http://www.webmd.com/diabetes/news/20140916/high-fat-dairy-diabetes.
  7. Tobias DK, Chen M, Manson JE, et al.  Effect of low-fat diet interventions versus other diet interventions on long-term weight change in adults: a systematic review and meta-analysis.
    The Lancet Diabetes & Endoocrinology. 2015.