Katherine M. Phillips

Diet Composition Validation for Clinical Feeding Trials

The actual nutrient intake from diets formulated for controlled feeding trials may differ from what is calculated using food composition data, due to known variability in the food supply and potential changes during food preparation. Calculated nutrient intake can therefore result in misleading or incorrect conclusions about the relationship between nutrient intake and outcome variables. Yet, most diet studies have not included validation of actual dietary intake by chemical analysis of diet samples

Food Composition Research and Food Composition Databases

Since 1997, I have worked in collaboration with the USDA Nutrient Data Laboratory (now the Methods, Analysis, and Food Composition Laboratory) to update and improve the data in the USDA National Nutrient Database for Standard Reference (SR)  on an ongoing basis, using nationwide, statistically-based food sampling, analytical quality control materials, and validated methodology for nutrients and other bioactive components. My laboratory collects and stores, logs, and tracks sample information including for nationwide samples of foods, prepares analytical homogenates and stores subsamples for nutrient and bioactive component analysis and maintains long term sample archives, distributes samples for analysis at other laboratories, performs analysis of select nutrients, develops matrix-matched control composites, designs and implements analytical quality control protocols. Prior to this work, data in the National Nutrient Database (now Food Data Central, FDC) were not generated according to standardized sampling and analysis protocols and were not always up-to-date with changes in the food supply.

Trans fatty acids in foods 

Background: Trans fatty acids found in partially hydrogenated vegetable oils have been associated with increased cardiovascular disease risk. This known risk led to regulations requiring labeling of the trans fat content of foods and efforts to eliminate trans fats in food products. Trans fatty acids also occur naturally in ruminant animal fats. Existing analytic methods, however, were giving inconsistent and inaccurate measurement of the trans fat content, particularly at low levels or in foods containing a mixture of fats. Thus, methods were needed for the accurate quantitation of trans fatty acids especially for foods in which the fat source was unknown, to account for naturally occurring isomers as well as to generate accurate data on the trans fat content of foods and diets.

Development of Methodology and Analysis of Bioactive Components in Foods

Background: Historically, epidemiological and clinical diet studies have focused on the relationship of nutrients and health outcomes. However, the contribution of other bioactive food components that vary among diets is a critical area of research, as these components are not typically controlled or quantified in trials targeting particular nutrients or diet composition and usually vary along with changes in foods consumed that lead to the difference in overall nutrient intake. One example is phytosterols, which have been shown to reduce detrimental levels of blood cholesterol and reduce the risk of heart disease. Phytosterols are at low/ non-existent levels in animal fats but high in vegetable oils, and dietary saturated fat are largely from animal foods and phytosterols and unsaturated fat from vegetable products. Likewise, environmental factors can cause significant changes in bioactive components, not reflected in average nutrient values in food composition databases.

Dr. Phillips' Bibliography Site

Roseland JM, Phillips KM, Patterson KY, Pehrsson PR, Bahadur R, Ershow AG, Somanchi M. Large variability of iodine content in retail cow's milk in the U.S. Nutrients. 2020 Apr 28;12(5).

McClure ST, Rebholz CM, Phillips KM, Champagne CM, Selvin E, Appel LJ. The percentage of dietary phosphorus excreted in the urine varies by dietary pattern in a randomized feeding study in adults. J Nutr. 2019 May 1;149(5):816-823.

Phillips KM, Haytowitz DB, Pehrsson PR. Implications of two different methods for analyzing total dietary fiber in foods for food composition databases. Journal of Food Composition and Analysis. 2019;84:103253.

Roseland, J. M., Phillips, K. M., Patterson, K. Y., Pehrsson, P. R., & Taylor, C. L. (2017). Vitamin D in Foods: An Evolution of Knowledge. In Vitamin D: Fourth Edition (Vol. 2, pp. 41-77).

Phillips KM, Rasor AS. A mixed mushroom control material to facilitate inter-laboratory harmonization of mushroom composition analyses. Journal of Food Composition and Analysis. 2016; 48:48-66.

Phillips KM, Council-Troche M, McGinty RC, Rasor AS, Tarrago-Trani M. Stability of vitamin C in fruit and vegetable homogenates stored at different temperatures. Journal of food composition and analysis. 2016; 45:147-162.

Roseland JM, Patterson K, Andrews KW, Phillips KM, Phillips MM, Pehrsson P, Dufresne GL, Jakobsen J, Gusev PA, Savarala S, Nguyen QV, Makowski AJ, Scheuerell CR, Laroche GP, Wise SA, Harnly JM, Williams JR, Betz JM, Taylor CL. Interlaboratory trial for measurement of vitamin D and 25(OH)D in foods and a dietary supplement using liquid chromatography-mass spectrometry. Journal of agricultural and food chemistry. 2016; 64(16):3167-3175.

Phillips KM, Pehrsson PR, Agnew WW, Scheett AJ, Follett JR, Lukaski HC, Patterson KY. Nutrient composition of selected U.S. traditional Northern Plains Native American plant foods. Journal of food composition and analysis. 2014; 34:136-152.

Phillips KM, Rasor AS. A nutritionally meaningful increase in vitamin D in retail mushrooms is attainable by exposure to sunlight prior to consumption. Journal of Nutrition and Food Sciences. 2013; 3(6):1000236.

Byrdwell WC, Harnly JM, Exler J, Patterson KY, Phillips KM, Holden JM. Vitamin D levels in fish and shellfish determined by liquid chromatography with ultraviolet detection and mass spectrometry. Journal of food composition and analysis. 2013; 30:109-119.

Exler J, Phillips KM, Patterson KY, Holden JM. Cholesterol and vitamin D content of eggs in the U.S. retail market. Journal of food composition and analysis. 2013; 29:110-116.

Phillips KM, Ruggio DM, Exler J, Patterson KY. Sterol composition of shellfish species commonly consumed in the United States. Food Nutr Res. 2012; 56.

Phillips KM, Horst RL, Koszewski NJ, Simon RR. Vitamin D4 in mushrooms. PLoS One. 2012;7(8):e40702. doi: 10.1371/journal.pone.0040702. Epub 2012 Aug 3.

Tarrago-Trani MT, Phillips KM, Cotty M. Matrix-specific method validation for quantitative analysis of vitamin C in diverse foods. Journal of food composition and analysis. 2012; 26:12-25.

Simon RR, Phillips KM, Horst RL, Munro IC. Vitamin D mushrooms: comparison of the composition of button mushrooms (Agaricus bisporus) treated postharvest with UVB light or sunlight. J Agric Food Chem. 2011 Aug 24;59(16):8724-32.

Phillips KM, Ruggio DM, Horst RL, Minor B, Simon RR, Feeney MJ, Byrdwell WC, Haytowitz DB. Vitamin D and sterol composition of 10 types of mushrooms from retail suppliers in the United States. J Agric Food Chem. 2011 Jul 27;59(14):7841-53.

Byrdwell WC, Exler J, Gebhardt SE, Harnly JM, Holden JM, Horst RL, Patterson KY, Phillips KM, Wolf WR. Liquid chromatography with ultraviolet and dual parallel mass spectrometric detection for analysis of vitamin D in retail fortified orange juice. Journal of food composition and analysis. 2011; 24(3):299-306.

Phillips KM, Ruggio DM, Haytowitz DB. Folate composition of 10 types of mushrooms determined by liquid chromatography–mass spectrometry. Food chemistry. 2011; 129:630-636.

Trainer D, Pehrsson PR, Haytowitz DB, Holden JM, Phillips KM, Rasor AS, Conley NA. Development of sample handling procedures for foods under USDA's National Food and Nutrient Analysis Program. J Food Compost Anal. 2010 Dec 1;23(8):843-851.

Patterson KY, Phillips KM, Horst RL, Byrdwell WC, Exler J, Lemar LE, Holden JM. Vitamin D content and variability in fluid milks from a US Department of Agriculture nationwide sampling to update values in the National Nutrient Database for Standard Reference. J Dairy Sci. 2010 Nov;93(11):5082-90.

Carlsen MH, Halvorsen BL, Holte K, Bøhn SK, Dragland S, Sampson L, Willey C, Senoo H, Umezono Y, Sanada C, Barikmo I, Berhe N, Willett WC, Phillips KM, Jacobs DR Jr, Blomhoff R. The total antioxidant content of more than 3100 foods, beverages, spices, herbs and supplements used worldwide. Nutr J. 2010 Jan 22;9:3.

Phillips KM, Ruggio DM, Howe JC, Leheska JM, Smith SB, Engle T, Rasor AS, Conley NA. Preparation and characterization of control materials for the analysis of conjugated linoleic acid and trans-vaccenic acid in beef. Food research international. 2010; 43:2253-2261.

Phillips KM, Ruggio DM, Ashraf-Khorassani M, Eitenmiller RR, Cho S, Lemar LE, Perry CR, Pehrsson PR, Holden JM. Folic acid content of ready-to-eat cereals determined by liquid chromatography-mass spectrometry: comparison to product label and to values determined by microbiological assay. Cerealchemistry. 2010; 87(1):42-49.

Phillips KM, Ruggio DM, Amanna KR. Optimization of standard gas chromatographic methodology for the determination of trans fat in unlabeled bakery products. Food analytical methods. 2010; 3:277-294.

Phillips KM, Tarrago-Trani MT, Gebhardt SE, Exler J, Patterson KY, Haytowitz DB, Pehrsson PR, Holden JM. Stability of vitamin C in frozen raw fruit and vegetable homogenates. Journal of food composition and analysis. 2010; 23:253-259.

Racette SB, Spearie CA, Phillips KM, Lin X, Ma L, Ostlund RE Jr. Phytosterol-deficient and high-phytosterol diets developed for controlled feeding studies. J Am Diet Assoc. 2009 Dec;109(12):2043-51.

Phillips KM, Carlsen MH, Blomhoff R. Total antioxidant content of alternatives to refined sugar. J Am Diet Assoc. 2009 Jan;109(1):64-71.

Phillips KM, Rasor AS, Ruggio DM. Folate content of different edible portions of vegetables and fruits. Nutrition and food sciences. 2008; 38(2):175-181.

Phillips KM, Ruggio DM, Amanna KR. Extended validation of a simplified extraction and gravimetric determination of total fat to ed foods. Journal of food lipids. 2008; 15:309-325.

Phillips, K.M., Byrdwell, W.C., Exler, J., Harnly, J., Holden, J.M., Holick, M.F., Hollis, B.W., Horst, R.L., Lemar, L.E., Patterson, K.Y., Tarrago-Trani, M.T., and Wolf, W.R. (2008). Development and validation of control materials for the measurement of vitamin D3 in ed U.S. foods. J. Food Comp. Anal., 21:527-534. Journal of food composition and analysis. 2008; 21:527-534.

Berglund L, Lefevre M, Ginsberg HN, Kris-Etherton PM, Elmer PJ, Stewart PW, Ershow A, Pearson TA, Dennis BH, Roheim PS, Ramakrishnan R, Reed R, Stewart K, Phillips KM. Comparison of monounsaturated fat with carbohydrates as a replacement for saturated fat in subjects with a high metabolic risk profile: studies in the fasting and postprandial states. Am J Clin Nutr. 2007 Dec;86(6):1611-20.

Phillips KM, Wolf WR, Patterson KY, Sharpless KE, Holden JM. Reference materials to evaluate measurement systems for the nutrient composition of foods: results from USDA's National Food and Nutrient Analysis Program (NFNAP). Anal Bioanal Chem. 2007 Sep;389(1):219-29.

Phillips KM, Patterson KY, Wolf WR, Sharpless KE, Amanna KR, Holden JM. K.E., Amanna, K.R., and Holden, J.M. (2007). Summary of Reference materials for the determination of the nutrient composition of foods. Accreditation and quality assurance. 2007; 12:126-133.

Phillips KM, Ruggio DM, Ashraf-Khorassani M, Haytowitz DB. Difference in folate content of green and red sweet peppers (Capsicum annuum) determined by liquid chromatography-mass spectrometry. J Agric Food Chem. 2006 Dec 27;54(26):9998-10002.

Halvorsen BL, Carlsen MH, Phillips KM, Bøhn SK, Holte K, Jacobs DR Jr, Blomhoff R. Content of redox-active compounds (ie, antioxidants) in foods consumed in the United States. Am J Clin Nutr. 2006 Jul;84(1):95-135.

Tarrago-Trani MT, Phillips KM, Lemar LE, Holden JM. New and existing oils and fats used in products with reduced trans-fatty acid content. J Am Diet Assoc. 2006 Jun;106(6):867-80.

Phillips KM, Patterson KY, Rasor AS, Exler J, Haytowitz DB, Holden JM, Pehrsson PR. Quality-control materials in the USDA National Food and Nutrient Analysis Program (NFNAP). Anal Bioanal Chem. 2006 Mar;384(6):1341-55.

Pehrsson PR, Perry CR, Patterson KY, Wilger J, Haytowitz DB, Holden JM, Day CD, Himes JH, Harnack L, Levy S, Wefel J, Heilman J, Phillips KM, Rasor AS. Sampling and initial findings for a study of fluoride in drinking water in the United States. Journal of food composition and analysis. 2006; 19:S45-S52.

Phillips KM, Ruggio DM, Ashraf-Khorassani M. Phytosterol composition of nuts and seeds commonly consumed in the United States. J Agric Food Chem. 2005 Nov 30;53(24):9436-45.

Koontz JL, Phillips KM, Wunderlich KM, Exler J, Holden JM, Gebhardt SE, Haytowitz DB. Comparison of total folate concentrations in foods determined by microbiological assay at several experienced U.S. commercial laboratories. J AOAC Int. 2005 May-Jun;88(3):805-13.

Phillips KM, Wunderlich KM, Exler J, Holden JM, Gebhardt SE, Haytowitz DB, Beecher GR, Doherty RF. Stability of 5-methyltetrahydrofolate in fresh frozen fruits and vegetables. Food chemistry. 2005; 94(2):587-595.

Phillips KM, Ruggio DM, Ashraf-Khorassani M. Analysis of steryl glucosides in foods and dietary supplements by solid-phase extraction and gas chromatography. Journal of food lipids. 2005; 12:124-140.

Phillips KM, Ruggio DM, Toivo JI, Swank MA, Simpkins AH. Free and esterified sterol composition of edible oils determined by solid-phase extraction and gas-liquid chromatography. Journal of food composition and analysis. 2002; 15:123-142.

Phillips KM, Simpkins AH, Amanna KR, Wolf W, Stewart KK, Clark S, Kim KP, Beecher GR, Holden J. Long-term stability of nutrients in a frozen mixed food control material. Fresenius J Anal Chem. 2001 Jun;370(2-3):297-302.

Toivo J, Phillips K, Lampi A, Piironen V. Determination of sterols in foods: recovery of free, esterified, and glycosidic sterols. Journal of food composition and analysis. 2001; 14(6):631-643. Holliday R, Phillips KM. Health benefits of the sunflower kernel. Cereal foods world. 2001; 46(5):205-208.

Phillips KM, Stewart KK. Well-Controlled Diet Studies in Humans: A Practical Guide to Design and Management. Dennis BH, Ershow A, Obarzanek E, Clevidence B, editors. Chicago, IL: American Dietetic Association; 1999. Chapter 22, Validating diet composition by chemical analysis; p.336-367.

McCullough ML, Karanja NM, Lin PH, Obarzanek E, Phillips KM, Laws RL, Vollmer WM, O'Connor EA, Champagne CM, Windhauser MM. Comparison of 4 nutrient databases with chemical composition data from the Dietary Approaches to Stop Hypertension trial. DASH Collaborative Research Group. J Am Diet Assoc. 1999 Aug;99(8 Suppl):S45-53.

Karanja NM, Obarzanek E, Lin PH, McCullough ML, Phillips KM, Swain JF, Champagne CM, Hoben KP. Descriptive characteristics of the dietary patterns used in the Dietary Approaches to Stop Hypertension Trial. DASH Collaborative Research Group. J Am Diet Assoc. 1999 Aug;99(8 Suppl):S19-27.

Phillips KM, Stewart KK, Karanja NM, Windhauser MM, Champagne CM, Swain JF, Lin PH, Evans MA. Validation of diet composition for the Dietary Approaches to Stop Hypertension trial. DASH Collaborative Research Group. J Am Diet Assoc. 1999 Aug;99(8 Suppl):S60-8.

Phillips KM, Tarrago-Trani MT, Stewart KK. Phytosterol content of experimental diets differing in fatty acid composition. Food chemistry. 1999; 64(3):415-422.

Phillips KM, Ruggio DM, Bailey JA. Precise quantitative determination of phytosterols, stanols, and cholesterol metabolites in human serum by capillary gas-liquid chromatography. Journal of chromatography B: biomedical sciences and applications. 1999; 732(1):17-29.

Toivo J, Phillips K, Lampi A, Piironen V. Plant sterols and cholesterol in different types of diets. In: Advances in Plant Lipid Research. Sanchez J, Cerda-Olmedo G, Martinez-Force E, editors. Spain: Universidad de Sevilla; 1998. p.478-480.

Dennis BH, Stewart P, Wang CH, Champagne C, Windhauser M, Ershow A, Karmally W, Phillips K, Stewart K, Van Heel N, Farhat-Wood A, Kris-Etherton PM. Diet design for a multicenter controlled feeding trial: the DELTA program. Delta Research Group. J Am Diet Assoc. 1998 Jul;98(7):766-76.

Ginsberg HN, Kris-Etherton P, Dennis B, Elmer PJ, Ershow A, Lefevre M, Pearson T, Roheim P, Ramakrishnan R, Reed R, Stewart K, Stewart P, Phillips K, Anderson N. Effects of reducing dietary saturated fatty acids on plasma lipids and lipoproteins in healthy subjects: the DELTA Study, protocol 1. Arterioscler Thromb Vasc Biol. 1998 Mar;18(3):441-9.

Kris-Etherton PM, Etherton TD, Pearson TA, Phillips K, Reed R, Windhauser M, Champagne C, Lefevre M. Stanol supplemented margarine (SM) lowers LDL C in moderately hypercholesterolemic subjects fed an average American diet (AAD). FASEB journal. 1998; 12.

Phillips KM, Lugogo RD, Harris RF, Tarrago-Trani MT, Bailey JA, Stewart KK. Direct determination of trans-octadecenoic acid in diet composites using a combination of silver ion-high performance liquid chromatography and capillary gas chromatography. Journal of food lipids. 1997; 4(3):173-188.

Phillips KM, Tarrago-Trani MT, Grove TM, Gruen I, Lugogo R, Harris RF, Stewart KK. Simplified gravimetric determination of total fat in food composites after chloroform-methanol extraction. Journal of the American Oil Chemists' Society. 1997; 74(2):137-142.

Cranker KJ, Phillips KM, Gonzales MC, Stewart KK. Effect of seeds on bile-enzymatic-gravimetric analysis of total dietary fiber. Journal of the AOAC International. 1997; 80(1):89-94.

Cranker KJ, Phillips KM, Gonzales MC, Stewart KK. Fine tuning a bile-enzymatic-gravimetric total dietary fiber method. Journal of the AOAC International. 1997; 80(1):89-94.

Phillips K. Diet composition validation and monitoring as part of a multicenter clinical feeding trial of step 1, high monounsaturated fat, and average american diets. FASEB journal. 1996; 10(3):A462.

Phillips KM. Effect of freeze-drying and heating during analysis on dietary fiber in cooked and raw carrots. Journal of agricultural and food chemistry. 1991; 39(7):1216-1221.

Wightman JP, Glanville JO, Hollenhead JB, Phillips KM, Tisa KN. Heats of immersion of bituminous coals in liquids. ACS division of fuel chemistry, preprints. 1987; 32(1):205-208.

Phillips KM, Glanville JO, Wightman JP. Heat of immersion of Virginia-C coal in water as a function of surface oxidation. Colloids and surfaces. 1986; 21:1-8.

Glanville JO, Hall ST, Messick DL, Newcomb KL, Phillips KM, Webster F, Wightman JP. Heat of immersion in water of Wyodak No. 3 coal as a function of moisture content. Fuel. 1986; 65(5):647-649.

Phillips KM, Wightman JP. Adsorption from binary solutions of polar n-decyl derivatives and heptane onto alumina. Journal of colloid and interface science. 1985; 108(2):495-502.

Gopel W, Anderson JA, Frankel D, Jaehnig M, Phillips K, Schafer JA, Rocker G. Surface defects ofTiO2(110): A combined XPS, XAES AND ELS study. Surface science. 1984; 139:333-346.

1987 Recipient, IFT graduate scholarship

1982-present: Phi Beta Kappa, Phi Kappa Phi, Phi Sigma