- 26 subjects participated in a 56-day study where they consumed 100g of Emmental cheese, 20g of butter, and 40g of almonds daily, providing an extra 760 kcal per day mainly from dairy fat. - The concentrations of four fatty acids (C14:0, C15:0, tC16:1, C17:0) suggested to be biomarkers for dairy consumption were measured before and after the overfeeding period. - Only the concentrations of C15:0 and tC16:1 significantly increased after the overfeeding, supporting their use as biomarkers for dairy fat intake. C14:0 and C17:0 levels did not change.

1. 1 Medical Research Council Human Nutrition Research, Elsie Widdowson Laboratory, Fulbourn Road, Cambridge, United Kingdom
2 Rhône-Alpes Research Center in Human Nutrition (CRNH-RA), Centre Hospitalier Lyon Sud, Pierre-Bénite, France,
3 Center for European Nutrition and Health (CENS), Pierre-Bénite, France,
4 Research Laboratory CarMeN, Lyon 1 University, INSERM UMR1060, Oullins, France,
Contact: kevin.seyssel@chu-lyon.fr
Jenkins B.1, Seyssel K.2,3,4, Summerhill K.1, Alligier M.2,3,4, Laville M.2,3,4, and Koulman A.1
Dairy fat biomarker response to dairy fat
overfeeding
2.a. Subjects : 26 subjects participated in the study. All subjects had normal fasting plasma glucose, cholesterol and triglycerides concentrations,
reported less than 4 hours of physical activity per week and were non-smokers.
2.b. Design of the study : The study consisted in 56 days of overfeeding during which the subjects were instructed to add to their usual daily diet, 100
grams of Emmental cheese, 20 grams of butter and 40 grams of almonds representing an excess of 760 kcal/day with 70g of lipids mainly composed of
dairy fat. During the study, the subjects were requested to maintain their usual eating behavior and also to maintain their regular level of physical activity.
To evaluate the adherence to the intervention the subjects completed a 5-d dietary records before the study and during the overfeeding period. Plasma
phospholipid fraction was obtained by solid phase extraction (SPE) followed by phospholipid fatty acid derivatisation by 14% Boron trifluoride methanol
solution, with gas chromatography flame ionisation detection.
3. Results : the effects of overfeeding on the dairy biomarkers
Figure 1: Design of the study
5. References :
1. Brevik A, Veierod MB, Drevon CA, Andersen LF. Evaluation of the odd fatty acids 15:0 and 17:0 in serum and adipose tissue as markers of intake of milk and dairy fat. Eur J Clin Nutr. 2005 Aug 24;59(12):1417-22.
2. Sofie Biong A, Berstad P, Pedersen JI. Biomarkers for intake of dairy fat and dairy products. European Journal of Lipid Science and Technology. 2006;108(10):827-34.
2. Fritsche J, SteinhartH. Contents of trans fatty acids (TFA) in German foods and estimation of daily intake. Fett/Lipid. 1997 Jan 1;99(9):314-8
3. Lim TK. Edible Medicinal And Non-Medicinal Plants: Volume 4. Springer; 2012. 1037p.
4. Conclusion : In conclusion, trans-palmitoleic acid (tC16:1) and pentadecanoic acid (C15:0) have a good correlation with dietary dairy fat intake, whereas
tetradecanoic acid (C14:0) and heptadecanoic acid (C17:0) do not, therefore hinting at either a possible endogenous productions or other dietary sources.
Therefore, odd chain fatty acids do not exclusively come from ruminant sources.
1.a. Context: Tetradecanoic acid (C14:0), pentadecanoic acid (C15:0), trans-palmitoleic acid (tC16:1) and heptadecanoic acid (C17:0) are suggested to be
biomarkers of dairy consumption (1;2). If the four above mentioned fatty acids are true intake markers of dairy fat, the concentration should increase
significantly after two months of dietary supplementation of diary fat.
1.b. Objective: The aim of this study was to assess the effect of a high-fat overfeeding composed with dairy foods on plasma dairy biomarkers.
2.c. Statistical analysis : All data are presented as mean ± SEM. Comparisons between time points (D0 vs. D56) were performed using a Student paired
T test or using Wilcoxon test when data where not normally distributed. A value of p<0.05 was considered significant.
PPL-FA level
(%) day = 0
PPL-FA level (%)
day = 56
PPL-FA change
(%) day = 0 -
56
Average relative
increase (%)
p value
(C14:0) 0.54 0.56 +0.02 4 0.48
(C15:0) 0.28 0.31 +0.03 10 0.02
(tC16:1) 0.06 0.07 +0.01 17 0.004
(C17:0) 0.45 0.46 +0.01 3 0.32
Day 0 Day 56 p value
n 26 26
Energy intake (kcal/day) 2236±71 3040±76 <0.001
Protein intake (g/day) 92.1±3.1 127.0±3.0 <0.001
Carbohydrate intake (g/day) 254.3±8.4 270.6±10.9 0.054
Lipid intake (g/day) 93.6±4.7 160.3±5.1 <0.001
Mono-instaturated fatty acid (g/day) 28.5±1.7 52.1±1.9 <0.001
Poly-insaturated fatty acid (g/day) 11.2±0.8 19.6±1.1 <0.001
Saturated fatty acid (g/day) 35.7±2.1 62.9±1.8 <0.001
Dairy product intake (g/day) 234.1±23.7 308.1±23.7 <0.001
Table 2: Mean (+SEM) 5-d dietary records before the study (D0) and
during the overfeeding period (D56) .
The lipid intake significantly increased during the overfeeding period
(+66.7g) associated with a significant increase of dairy products
intake. Mono-insaturated, poly-insaturated and saturated fatty acids
significantly increased during overfeeding due to the consumption of
cheese, butter and almonds,
Table 4: The fatty acid concentrations, of the plasma phospholipid fraction (PPL-FA),
analysed by GC-FID. C14:0, C15:0, tC16:1 and C17:0.
Among the four fatty acids representing potential dairy biomarkers only C15:0
and tC16:1 level significantly increased at the end of the overfeeding. C14:0 and
C17:0 levels did not change after the 56-days of overfeeding.
Table 1: The concentration of the fatty acids that literature has shown a correlation
of dietary intake reflected in the plasma fatty acids concentration. C14:0, C15:0,
tC16:1 and C17:0 for each fat source consumed within the study intervention (3;4).
Emmental Cheese
(mg/100g)
Unsalted Butter
(mg/100g)
Almonds (dried)
(mg/100g)
Overfeeding
mg/day
(C14:0) 3000 8700 23 4749
(C15:0) 350 880 8 529
(tC16:1) 50 190 12 92
(C17:0) 200 330 30 278
1
D0 High-fat overfeedingVisit of
selection
? 5-d dietary record
Anthropometric measurements
MRI: abdominal fat mass ditribution
DEXA: body composition
Blood samples
D56
?
Day 0 Day 56 p value
Body weight (kg) 79.1±1.8 81.6±1.8 <0.001
Fat mass (%) 19.6±0.8 20.3±0.8 <0.001
Subcutaneous adipose tissue (cm3) 91±7 100±7 <0.001
Visceral adipose tissue (cm3) 92±11 102±1 <0.001
Table 3: Anthropometric parameters before and after overfeeding