Research

IFAC Publishes Research on Phosphorus Intake and Health Using NHANES Data

Findings from a new two-part research study supported by IFAC

Research supported by the International Food Additives Council (IFAC) recently examined trends of dietary phosphorus intake in Americans and potential implications for health and physiology.

Phosphorus is an essential mineral, naturally present in many foods. The body uses phosphorus to build strong bones and teeth, maintain a normal pH balance, deliver oxygen to tissues, convert food into energy, and maintain muscle function. Naturally-occurring phosphorus is found primarily in protein-rich foods such as meat, poultry, fish and dairy, as well as in whole grains, beans, lentils, and nuts. It is found in smaller amounts in vegetables and fruits. Sources of added phosphorus include flavored waters, iced teas, sodas and bottled coffee beverages, and nondairy creamers.

A two-part study by Kristin Fulgoni, Victor Fulgoni, and Taylor Wallace examined trends in phosphorus content in foods using NHANES data and the effects of dietary phosphorus intake on human health and physiology. Currently, the average total phosphorus intake for adult Americans is 1,400 milligrams per day, which is well below the tolerable maximum of 4,000 milligrams per day. Added phosphorus accounts for around 12% of total phosphorus intake among American adults over age 19.

One finding was that increased phosphorus correlated with higher bone mineral content and bone density. However, for every 100 milligrams of added phosphorus consumed, adults had a 21% greater chance of having lower HDL cholesterol (or “good” cholesterol) levels. Finally, higher total phosphorus intake was found to be correlated with a 3% decrease in the risk of high blood pressure.

These new findings bolster transparency within the food industry by illustrating how much phosphorus in the form of phosphate food additives is added to foods. In the interest of public health and safety, food companies should continue to examine the possible impacts their products have on consumer health and physiology.

Abstract: Trends in Intake Paper

Dietary phosphorus intake in the USA has been consistently greater than the Recommended Daily Allowance (RDA) with several studies reporting associations between intake and health risks as well as all-cause mortality within healthy subjects and patients with chronic kidney disease (CKD). The current study utilized a novel approach to calculate added phosphorus content in foods to determine sources (National Health and Nutrition Examination Survey, NHANES 2001–2016, n = 39,796) and trends in consumption (NHANES 1988–1994, 2001–2016, n = 55,744) of total, naturally occurring, and added phosphorus. Among adults (19+ years), the mean intake of total and natural phosphorus (mg/day) in 1988–1994 as compared with 2015–2016 increased (total: 1292 ± SE 11 vs. 1398 ± SE 17; natural: 1113 ± SE 10 vs. 1243 ± SE 16 mg/day); in contrast, added phosphorus intake decreased during this time (178 ± SE 2.9 vs. 155 ± SE 4.1 mg/day). Added phosphorus as a percent of total ranged from about 14.6% in 1988–1994 to about 11.6% in 2015–2016. The top five sources of total and naturally occurring phosphorus, representing approximately 20% of intake, were cheese, pizza, chicken (whole pieces), reduced-fat milk, and eggs/omelets. The top five sources of added phosphorus were cheese, soft drinks, cakes/pies, rolls/buns, and cookies/brownies, representing 45% of added phosphorus in the diet. Consumption of added phosphorus has decreased over the past few decades, possibly due to increased demand for foods with less additives/ingredients but may also be due to inaccurate phosphorus values in nutrition databases. Further studies are needed to validate the added phosphorus calculations utilized in this study and nutrition databases should consider providing added phosphorus content.

Abstract: Association with Health Paper

Dietary phosphorus intake in the USA has been consistently greater than the Recommended Daily Allowance (RDA) with several studies reporting associations between intake and health risks as well as all-cause mortality within healthy subjects and patients with chronic kidney disease (CKD). The current study utilized a novel approach to calculate added phosphorus content in foods to determine sources (National Health and Nutrition Examination Survey, NHANES 2001–2016, n = 39,796) and trends in consumption (NHANES 1988–1994, 2001–2016, n = 55,744) of total, naturally occurring, and added phosphorus. Among adults (19+ years), the mean intake of total and natural phosphorus (mg/day) in 1988–1994 as compared with 2015–2016 increased (total: 1292 ± SE 11 vs. 1398 ± SE 17; natural: 1113 ± SE 10 vs. 1243 ± SE 16 mg/day); in contrast, added phosphorus intake decreased during this time (178 ± SE 2.9 vs. 155 ± SE 4.1 mg/day). Added phosphorus as a percent of total ranged from about 14.6% in 1988–1994 to about 11.6% in 2015–2016. The top five sources of total and naturally occurring phosphorus, representing approximately 20% of intake, were cheese, pizza, chicken (whole pieces), reduced-fat milk, and eggs/omelets. The top five sources of added phosphorus were cheese, soft drinks, cakes/pies, rolls/buns, and cookies/brownies, representing 45% of added phosphorus in the diet. Consumption of added phosphorus has decreased over the past few decades, possibly due to increased demand for foods with less additives/ingredients but may also be due to inaccurate phosphorus values in nutrition databases. Further studies are needed to validate the added phosphorus calculations utilized in this study and nutrition databases should consider providing added phosphorus content.

Dietary Exposures to Common Emulsifiers and Their Impact on the Gut Microbiota: Is There a Cause for Concern?

Scientific Review Supports Safety of Emulsifiers in Relation to the Human Microbiome

In 2007, the National Institutes of Health’s Human Microbiome Project dramatically increased interest in the human gut microbiota, also called the microbiome. Consumers, health professionals and scientists want to know more about the relationship between the microbiome and our health, including how foods and beverages may have an influence on the function and makeup of the microbiome. A review, “Dietary Exposures to Common Emulsifiers and Their Impact on the Gut Microbiota: Is There a Cause for Concern?,”1 published in the journal Comprehensive Reviews in Food Science and Food Safety, provided an update on the science related to how select food ingredients known as emulsifiers, affect the microbiome. The study’s authors found that this category of food ingredients does not pose any negative effect on the microbiome. 

What is the microbiome?

The microbiome is the collection of trillions of microorganisms, mainly found in the gastrointestinal tract. Developedat birth, the microbiome rapidly develops over the first three years and continues to change and adapt throughout our lives, changing in response to various factors including diet. While over 1000 species of microorganismshave been identified in the microbiome, there are about 160 within the gut of any one individual. The microbiome plays a key role in human digestion and metabolism by contributing enzymes not produced by the body to help break down polysaccharides and polyphenols, and synthesize vitamins. 

Diet and the Microbiome

Research shows that the gut microbiome changes in response to diet, both in the short- and long-term.  But what do these changes mean? Overall, studies indicate that the composition and function of the microbiome is modified by diet. However, everyone responds differently to various dietary components and that includes our microbiomes. Therefore, in order to properly assess the effects of individual ingredients or components of a diet on the microbiome, it is critical that the diets of subjects participating in such studies are carefully controlled, and subjects’ usual, or baseline, diets are well documented and understood.  

What are emulsifiers?

Given the recent questions around diet and the microbiome, specifically around emulsifiers, Vo et al.1conducted a literature search to review the existing scientific evidence on how emulsifiers impact the microbiome.  The ingredients in this review include:

  • Carboxymethyl cellulose
  • Polysorbate 80
  • Gum Arabic
  • Carrageenan
  • Arabinogalactan

These emulsifiers are often used in foods for the purposes of achieving preferred flavors or to improve texture, stability and shelf life. Without emulsifiers, packaged foods such as salad dressings, chocolate bars and ice cream would not exist. The ubiquity of these ingredients in the food supply has drawn increased questioning related to health-outcomes that are often associated with dietary patterns, including type 1 and type 2 diabetes, metabolic disease and irritable bowel disease (IBD). Changes in the microbiome, regarding structure and function have been observed in populations with metabolic syndrome, which includes disease states such as obesity, hypertension, diabetes, and cardiovascular disease. 

So what does the science tell us?

In short, there is limited evidence indicating adverse effects of emulsifiers on the microbiome. This is due to a number of issues including: 

  • There are inconsistencies in the methodologies used to analyze the microbiome between studies. The differing techniques used from study to study affect the bacteria that are identified and at what abundance.  Thus, there are inconsistent findings and interpretations that follow. 
  • Anatomical and physiological differences in the gastrointestinal tract of rodents and humans makes it difficult to extrapolate findings in rodents to humans. 
  • Test diets provided to laboratory animals can be controlled in animal studies while the human diet cannot be adequately controlled.
  • There is no alignment on what type of changes in the microbiome qualify as being adverse. 

The researchers of this review suggest that an established and agreed upon range of different microorganisms within the microbiome would help to provide a reference for future studies in the interpretation and clinical relevance of changes observed in response to various dietary components and ingredients.  Given this, the researchers state that they have found that consumption of foods with emulsifiers do not pose any safety concerns and that their history of safe use is not brought into question by the existing scientific literature.