Synne Groufh-Jacobsen

• Mulkerrins, Isabelle; Medin, Anine Christine; Groufh-Jacobsen, Synne; Margerison, Claire & Larsson, Christel (2025). Micronutrient intake and nutritional status in 16-to-24-year-olds adhering to vegan, lacto-ovo-vegetarian, pescatarian or omnivorous diets in Sweden. European Journal of Nutrition. ISSN 1436-6207. 64. doi: 10.1007/s00394-025-03738-2. Full text in Research Archive Show summary

  Purpose The nutritional adequacy of plant-based diets for youth is of public health relevance but is insufficiently studied. This cross-sectional study aims to assess the micronutrient intake and nutritional status in youth adhering to vegan, lacto-ovo-vegetarian, pescatarian or omnivorous diets in Sweden. Methods Healthy 16-to-24-year-olds (n = 60 vegans, n = 59 lacto-ovo-vegetarians, n = 55 pescatarians, n = 61 omnivores) completed a 255-item web-based questionnaire, conducted four non-consecutive 24-hour dietary recalls, provided capillary blood samples and one spot urine sample. Usual micronutrient intakes were estimated by the Multiple Source Method. At the group level, risk of inadequate intake was defined as > 50% with intakes below average requirements. Samples were analysed for haemoglobin (HB), serum transferrin receptor (sTfR), homocysteine (tHcy), methylmalonic acid (MMA), 25-hydroxyvitamin D3 (25-OH-D3), and urinary iodine concentration (UIC).

• Mulkerrins, Isabelle; Medin, Anine Christine; Groufh-Jacobsen, Synne; Margerison, Claire & Larsson, Christel (2025). Dietary intake among youth adhering to vegan, lacto-ovo-vegetarian, pescatarian or omnivorous diets in Sweden. Frontiers in Nutrition. 12. doi: 10.3389/fnut.2025.1528252. Full text in Research Archive Show summary

  Objective: To assess the intakes of food groups, energy, and macronutrients among youth in Sweden who adhere to vegan, lacto-ovo-vegetarian, pescatarian or omnivorous diets. Further, to evaluate youth’s adherence to the food-based dietary guidelines (FBDG). Design: In this cross-sectional study, dietary intake data was obtained through repeated non-consecutive 24-h dietary recalls (24HDR) and a dietary screener assessing consumption frequency of food groups. Usual daily intakes were estimated using the Multiple Source Method (MSM), and for usual intakes of food groups the 24HDR intake data was combined with consumption frequency. Setting: Gothenburg, Sweden, December 2022–January 2024. Participants: In total 235 youth (78% female, mean age 22 ± 2 years), consisting of 60 vegans, 59 lacto-ovo-vegetarians, 55 pescatarians, and 61 omnivores. Results: For usual intakes (median value), both g/d and g/MJ, all plant-based dietary groups had higher intakes of legumes and plant-based meat analogs compared to omnivores (for all, p < 0.001), and vegans and lacto-ovo-vegetarians had higher intakes of plant-based dairy substitutes (vs. pescatarians and omnivores, p < 0.001). Moreover, vegans had higher intakes of refined grain products (vs. pescatarians, p = 0.012), nuts/seeds (vs. pescatarians and omnivores, p = 0.002), and vegetable oil (vs. omnivores, p = 0.014). Omnivores had higher intakes of fried/premade potato dishes (vs. lacto-ovo-vegetarians and vegans, p < 0.001), and lower intakes of plain potatoes (vs. lacto-ovo-vegetarians and pescatarians, p < 0.001). Overall intakes of ‘sweets and snack foods’ did not differ between dietary groups. Omnivores had higher usual intakes of energy compared to lacto-ovo-vegetarians and pescatarians (10 vs. 9 MJ/d, p = 0.016). Most macronutrient recommendations were met across groups, except for carbohydrates (below for omnivores), fiber (below for omnivores and pescatarians), and saturated fatty acids (exceeded by all except vegans). For the FBDG for whole grains, omnivores (23%) had a higher adherence vs. vegans (2%) and lacto-ovo-vegetarians (3%), p < 0.001. No difference was found between dietary groups for adherence to the FBDG’s for fruits, berries, and vegetables (10%), nuts (24%), and vegetable oil (4%). Conclusion: Swedish youth, regardless of dietary practice, need to increase intakes of fruits, berries, vegetables, nuts, and whole grains, and limit consumption of discretionary foods to better align with food and nutrition recommendations.

• Groufh-Jacobsen, Synne; Larsson, Christel; Mulkerrins, Isabelle; Aune, Dagfinn & Medin, Anine Christine (2025). Food groups, macronutrient intake and objective measures of total carotenoids and fatty acids in 16-to-24-year-olds following different plant-based diets compared to an omnivorous diet. PLOS ONE. 20(1). doi: 10.1371/journal.pone.0311118. Full text in Research Archive Show summary

  Background Knowledge about the diet quality among youth who follow different types of plant-based diets is essential to understand whether support is required to ensure a well-planned diet that meets their nutritional needs. This study aimed to investigate how food groups, macronutrient intake, and objective blood measures varied between Norwegian youth following different plant-based diets compared to omnivorous diet. Methods Cross-sectional design, with healthy 16-to-24-year-olds (n = 165) recruited from the Agder area in Norway, following a vegan, lacto-ovo-vegetarian, pescatarian, flexitarian or omnivore diet. Participants completed an electronic questionnaire, a dietary screener, 24-hour dietary recalls and provided dried blood samples for analysis of carotenoids and fatty acids. Results Vegans reported the highest mean intake (g/d, g/MJ) of vegetables, legumes, nuts and seeds and substitutes to dairy and meat (compared to all, p<0.001), fruit and berries (compared to omnivores, p = 0.004 and pescatarians, p = 0.007), and vegetable oil (compared to omnivores, p<0.001, pescatarians, p = 0.003 and flexitarians, p = 0.004) and vegetable products (compared to omnivores, p = 0.007). No difference was found between groups in mean intake (g/d, g/MJ) of any of the confectionary foods or sweet pastries, beverages (sugar-sweetened, non-sugary, alcoholic), or salted snacks, neither in g/MJ of convenience foods. The energy percentage (E%) of protein, carbohydrates and total fat were within the Nordic Nutrition Recommendations 2023 across groups. However, all groups, except vegans, exceeded the E% for saturated fatty acids. All groups exceeded recommendations for added and free sugar. Furthermore, all groups consumed <25g/d of dietary fibre, except vegans and pescatarians. For omega-3, lacto-ovo-vegetarians had intakes below recommendations. Blood marker of total carotenoids did not differ between groups, neither did the reported mean intake (g/MJ) of carotenoid-rich foods. Vegans showed the lowest blood level of palmitic acid compared to all (p<0.001), but highest level of linoleic acid (compared to flexitarians, p = 0.022, and omnivores, p<0.001). The lowest blood levels of eicosapentaenoic acid and docosahexaenoic acid were found in vegans and lacto-ovo-vegetarians. Conclusions Our findings suggest that all groups had risk of dietary shortcomings. However, vegans consumed the most favorable diet. All groups should increase their consumption of vegetables, fruits and berries, and reduce their total sugar intake.

• Medin, Anine Christine; Gulowsen, Stine Rambekk; Groufh-Jacobsen, Synne; Berget, Ingunn; Grini, Ida Synnøve Bårvåg & Varela, Paula (2025). Definitions of ultra-processed foods beyond NOVA: a systematic review and evaluation. Food & Nutrition Research (FNR). ISSN 1654-6628. 69, p. 1–15. doi: 10.29219/fnr.v69.12217. Full text in Research Archive Show summary

  Background: Ultra-processed foods (UPFs) are associated with negative health outcomes, but current classification systems, including the dominant NOVA system, are typically not suitable for identifying which factors of these foods may be harmful. New ways of defining UPFs are needed to better understand how food processing affects health. Objective: To identify classification systems that include a category for ultra-processed or highly processed foods with a focus on comparing their definitions and provide a current evaluation of available alternatives to NOVA. Design: A systematic literature review was conducted following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, with the search strategy developed in collaboration with a university librarian. The literature search was completed on 18 December 2023, using databases Medline, Embase (via Ovid), and Web of Science. No human participants were included. Results: We identified six systems – NOVA, European Prospective Investigation into Cancer and Nutrition (EPIC), International Food Policy Research Institute (IFPRI), University of North Carolina (UNC), UnProcessed Pantry Project (UP3), and Siga – that categorize highly processed food or UPFs. These systems differ in structure and detail, with NOVA, EPIC, and Siga providing specific examples of processing techniques. Regarding additives, NOVA, Siga, and UP3 include them explicitly, with Siga offering the most detailed categorization based on additives and ingredients. Siga also includes quantitative measures for nutritional quality, including cut-offs for sugar, fat, and salt, while IFPRI and UP3 address nutritional quality non-quantitatively. Discussion: When comparing NOVA’s UPF category with the highly processed food or UPF categories used in the other five identified systems, we found that none specifies processing techniques clearly. Both NOVA and Siga define additives unique to their UPF categories. Siga stands out by addressing the diverse risks associated with additives and offering quantitative nutritional quality criteria, thus addressing some of the criticisms of how UPFs are commonly defined. Conclusions: Siga represents a valuable, but not final, step forward in classifying UPFs and could serve as a reference in developing a new operational definition for UPFs.

• Groufh-Jacobsen, Synne; Larsson, Christel; Margerison, Claire; Mulkerrins, Isabelle; Aune, Dagfinn & Medin, Anine Christine (2024). Micronutrient intake and status in young vegans, lacto-ovo-vegetarians, pescatarians, flexitarians, and omnivores. European Journal of Nutrition. ISSN 1436-6207. 63, p. 1–17. doi: 10.1007/s00394-024-03453-4. Full text in Research Archive Show summary

  Purpose: Whether youth who follow plant-based diets in Nordic countries meet their dietary needs for micronutrients remains unclear. This study aims to evaluate micronutrient intake and status in Norwegian youth following vegan, lacto-ovo-vegetarian, pescatarian, flexitarian and omnivore diets. Methods: Cross-sectional design, with healthy 16-to-24-year-olds (n = 165). Participants were asked to complete a questionnaire and four 24-hour dietary recalls. Dried blood spots (DBS) and spot-urine samples were collected for analysis of methyl malonic acid (MMA) (n = 65), haemoglobin (Hb) (n = 164) and urinary iodine concentration (UIC) (n = 163). Results: Vegans reported highest habitual supplement usage of multivitamin (58%), B12 (90%) and macroalgae consumption (32%), while flexitarians reported highest habitual usage of omega-3 supplements (56%). For daily supplement usage, vegans reported highest use of multivitamins (42%), B12 (79%), iodine (37%) and iron (63%). Increased risk of inadequate intake (energy-adjusted) were found for vitamin D (60% within lacto-ovo-vegetarians), selenium (70% within lacto-ovo-vegetarians, 65% within omnivores), and iodine (63% within vegans). Median MMA levels suggest low risk of insufficient B12 status across all groups (MMA 0.04‒0.37µmol/l) and 2% had MMA levels indicating possible B12 deficiency and 8% had elevated levels. Median Hb levels indicated low risk of anemia across all groups (≥ 12.0 females, ≥ 13.0 g/dl males), though 7% had Hb values indicating risk of mild anemia and 4% risk of moderate anemia. The median UIC indicates mild iodine deficiency in all groups (UIC < 100 µg/l), except vegans, who were moderately iodine deficient (UIC < 50 µg/l). Conclusions: Our study indicated that the participating youth had low risk of inadequate intake of most micronutrients, partly due to high supplement usage. However, for iodine, vitamin D, and selenium higher risk of inadequate intake was found. UIC corroborated the low iodine intake among vegans. Thus, we suggest iodine status of youth in Norway should be monitored, especially among young fertile women who omits dietary iodine sources, until a mandatory iodine fortification program is implemented. Furthermore, we suggest that food education on how to secure sufficient nutrients from food in general should be provided to the Norwegian youth population, especially how to secure adequate intake of vitamin D, selenium and iodine.

• Groufh-Jacobsen, Synne & Medin, Anine Christine (2023). Food literacy competencies in youth – a mini-review. Frontiers in Public Health. 11. doi: 10.3389/fpubh.2023.1185410. Full text in Research Archive Show summary

  Introduction: Young people’s transition into adulthood is an opportunity in the life course to establish adequate eating behaviors, hence exploring food literacy competencies in this period of life is especially important. Food literacy has recently gained increased attention in adults, adolescents, and younger children, but less is published about youth. This paper aims to summarize what tools have been used to measure food literacy and the sub-competence nutrition literacy in youth aged 16–24 years in the previous 5 years. Methods: A mini-literature review was conducted in MEDLINE and EMBASE via Ovid, in September 2022. Study eligible criteria; had to be an original article, using a tool to quantitatively assess food literacy and/or nutrition literacy, including participants between 16–24 years, full text available in English, published between 2017–2022. Results: A total of 958 articles were identified, of which 385 duplicates were removed. Thus, 573 articles were screened by title/abstract. Finally, nine articles were eligible for data extraction of which four proposed a tool to measure food literacy and five proposed a tool to measure nutrition literacy. Discussion and conclusion: Although four studies claimed to measure food literacy, none of these used tools comprehensive enough to measure all aspects of food literacy, and only one was validated in young people. This study shows that only few tools exist for the measurement of food literacy in youth, and those available are scant. Further work is needed to develop a food literacy tool for youth.

• Groufh-Jacobsen, Synne; Larsson, Christel; Daele, Wim Van; Margerison, Claire; Mulkerrins, Isabelle & Aasland, Lale Marie [Show all 7 contributors for this article] (2023). Food literacy and diet quality in young vegans, lacto-ovo vegetarians, pescatarians, flexitarians and omnivores. Public Health Nutrition (PHN). ISSN 1368-9800. p. 1–11. doi: 10.1017/S1368980023002124. Full text in Research Archive Show summary

  Objective: To investigate whether food literacy competencies and diet quality vary between 16-to-24-year-olds vegans, lacto-ovo vegetarians, pescatarians, flexitarians and omnivores and to assess whether food literacy is associated with diet quality. Design: Cross-sectional study. Food literacy (general nutrition knowledge, critical nutrition literacy and food skills) and diet quality were measured using an electronic questionnaire. Setting: Southern Norway, September 2021 – March 2022. Participants: Healthy 16–24-year-olds (n 165). Results: Overall, the mean general nutrition knowledge score was moderate (48·0 out of 67·0); the lowest mean score was found in omnivores and the highest in flexitarians (45·6 v. 51·5) (P = 0·034). The mean score of critical nutrition literacy was also moderate (3·7 out of 5·0); vegans showed higher scores compared to other dietary practices (P = 0·018). No difference was observed in food skills between the different dietary practices. The overall median diet quality score was 46·0 out of 80·0, lowest in omnivores and highest in vegans (42·0 v. 56·0) (P =< 0·001). In multivariate regression analyses, general nutrition knowledge, food skills and vegan dietary practice were significantly associated with higher diet quality. Conclusions: We found moderate levels of food literacy across all dietary practices. The food literacy competencies, general nutrition knowledge and food skills were associated with higher diet quality in our sample. Omnivores showed both the lowest general nutrition knowledge level and lowest diet quality scores. In contrast, both flexitarians and vegans scored highest on general nutrition knowledge and diet quality scores, despite being one of the less restrictive and one of the strictest plant-based dietary practices, respectively.

• Henjum, Sigrun; Groufh-Jacobsen, Synne; Aakre, Inger; Gjengedal, Elin Lovise Folven; Langfjord, Mina Marthinsen & Heen, Espen Kolstad [Show all 8 contributors for this article] (2023). Thyroid function and urinary concentrations of iodine, selenium, and arsenic in vegans, lacto-ovo vegetarians and pescatarians. European Journal of Nutrition. ISSN 1436-6207. 62, p. 3329–3338. doi: 10.1007/s00394-023-03218-5. Full text in Research Archive Show summary

  Purpose Populations following a plant-based diet may be at particular risk of thyroid dysfunction due to low iodine and selenium intakes. The main purpose was to assess thyroid function and urinary concentration of iodine, selenium, and arsenic, in subjects following a vegan, lacto-ovo vegetarian, or pescatarian diet. Methods In Norway, a country without mandatory dietary iodine fortification, 205 adults, following vegan (n = 115), lacto-ovo vegetarian (n = 55) and pescatarian diet (n = 35) were included. Thyroglobulin (Tg), thyroid-stimulating hormone (TSH), free triiodothyronine (fT3), free thyroxine (fT4), and serum anti-TPO (S-anti-TPO) were measured in a venous blood sample and concentrations of iodine (UIC), creatinine (UCC), selenium, and arsenic were measured from single spot urine samples. Results Subclinical hypothyroidism (TSH > 4.0 mU/L) was observed in 3% of subjects. The overall median (p25, p75) Tg was 17 (9, 30) µg/L and vegans had higher Tg compared to pescatarians. Vegans not consuming iodine-containing supplements (n = 43) had higher Tg, than supplement users (n = 72), 27 (11, 44) vs. 16 (8, 25) µg/L and higher fT4, 16 (15, 17) vs. 15 (14, 17) pmol/L, respectively. The overall median UIC was 57 (28, 130) µg/L, all dietary groups had median UIC below WHO thresholds. Median urinary selenium and arsenic concentration was 13 (6, 22) and 3 (2, 8) µg/L, respectively. Conclusion The prevalence of subclinical hypothyroidism was low and fT4 and fT3 were within the normal range for all dietary groups. Vegans had significantly increased Tg compared to pescatarians.

• Groufh-Jacobsen, Synne; Abel, Marianne Hope; Brantsæter, Anne Lise; Andersson, Maria; Meyer, Haakon Eduard & Henjum, Sigrun (2023). National monitoring of iodine, sodium, and vitamin d status in toddlers and women of childbearing age – results and lessons learned from a pilot study in norway. Food & Nutrition Research (FNR). ISSN 1654-6628. 67. doi: 10.29219/fnr.v67.9088. Full text in Research Archive Show summary

  Background: Norway is lacking a population-based national monitoring program for iodine, sodium, and vitamin D status.Objective: The aim of this study was to pilot-test a study design for collecting biological samples from a coun-try-representative sample of 2-year-old children and their mothers and to report results for iodine, salt, and vitamin D at baseline, before initiation of salt iodization in Norway.Design: In a cross-sectional study, we recruited 2-year-old children and their mothers during the routine 2-year check-up through 38 randomly selected health clinics in 2021. Spot urine samples were analyzed for iodine, creatinine, and sodium, and dried blood spots from the mothers were analyzed for thyroglobulin (Tg) and 25-hydroxyvitamin D (25(OH)D).Results: We aimed at including 400 mother–child pairs but recruited only 55 pairs. Major challenges were closed health clinics due to the COVID-19 pandemic, lack of motivation of the health personnel to prioritize recruiting, missing information about non-participation, and high workload for participants. The median urinary iodine concentration (UIC) was 123 (95% CI: 76, 228) μg/L in the toddlers and 83 (95% CI: 72, 99) μg/L in the mothers. The median urinary sodium concentration (UNaC) was 62 (95% CI: 37, 91) mmol/L in the toddlers and 93 (95% CI: 77, 107) mmol/L in the mothers. Of the mothers, 18% had levels of 25(OH)D <50 nmol/L (suboptimal status).Discussion and conclusion: Lessons learned from the pilot study will be used to design a national monitoring program for toddlers and women of childbearing age in Norway. The results indicate that 2-year-old children and women of childbearing age in Norway may have inadequate iodine intakes at the group level, while for vitamin D, most of the mothers had adequate status.

• Tonheim, Live Edvardsen; Groufh-Jacobsen, Synne; Stea, Tonje Holte & Henjum, Sigrun (2023). Consumption of meat and dairy substitute products amongst vegans, vegetarians and pescatarians. Food & Nutrition Research (FNR). ISSN 1654-6628. 67. doi: 10.29219/fnr.v67.9081. Full text in Research Archive Show summary

  Background: An increasing number of people adhere to plant-based diets, and the market for plant-based meat and dairy substitute products has been expanding rapidly. Objective: To examine total intake of macronutrients and salt in a sample of Norwegian vegans, vegetarians and pescatarians; the consumption frequency of plant-based meat and dairy substitutes and raw ingredients used in these products; and the contribution to total macronutrient and salt intake from these products. Design: A cross-sectional design using single 24-h dietary recall to assess the intake of macronutrients, salt and substitute products that the participants (n = 158 Norway residents [age 18–60 years]: vegans [n = 83]; vegetarians [n = 47]; pescatarians [n = 28]) consumed. The chi-square test with pairwise comparisons and the Kruskal-Wallis test with post hoc test were used to compare differences between diet groups. Macronutrient and salt intake were assessed relative to the Nordic Nutrition Recommendations (NNR). Results: Dietary macronutrient intake fell within NNR recommendations, with a favourable distribution of fatty acids and high levels of dietary fibre. Most of the vegans (90%), vegetarians (68%) and pescatarians (64%) consumed meat or dairy substitutes. The main raw ingredient in the substitute products was soy, followed by oats and peas. Overall, substitute products contributed to 12% of total energy and 16% of total salt intake. The substitute products contributed to higher saturated fatty acid (SFA) intake amongst vegans (27% of total SFA intake) compared with vegetarians (10%) and pescatarians (8%). Moreover, substitute products contributed to higher protein intake in vegans (19%) compared with pescatarians (7%). Conclusion: Most participants consumed meat or dairy substitute products, suggesting that these products are included regularly in Norwegian plant-based diets. Furthermore, substitute products may contribute to dietary fat, SFA and protein intake amongst vegans.

• Henjum, Sigrun; Groufh-Jacobsen, Synne; Allen, Lindsay H.; Raael, Ellen; Israelsson, Anna Maria & Shahab-Ferdows, Setareh [Show all 7 contributors for this article] (2022). Adequate vitamin B 12 and folate status of Norwegian vegans and vegetarians. British Journal of Nutrition. ISSN 0007-1145. 129(12), p. 2076–2083. doi: 10.1017/S0007114522002987. Full text in Research Archive Show summary

  Plant-based diets may increase the risk of vitamin B12 deficiency due to limited intake of animal-source foods, while dietary folate increases when adhering to plant-based diets. In this cross-sectional study, we evaluated the B12 and folate status of Norwegian vegans and vegetarians using dietary B12 intake, B12- and folic acid supplement use, and biomarkers (serum B12 [B12], plasma total-homocysteine [tHcy], plasma-methylmalonic acid [MMA], and serum-folate). Vegans (n=115) and vegetarians (n=90) completed a 24-hour dietary recall and a food-frequency questionnaire and provided a non-fasting blood sample. cB12, a combined indicator for evaluation of B12 status, was calculated. B12 status were adequate in both vegans and vegetarians according to the cB12 indicator, however 4% had elevated B12. Serum B12, tHcy, MMA concentrations and the cB12 indicator (overall median: 357pmol/L, 9.0µmol/L, 0.18µmol/L, 1.30 (cB12)) did not differ between vegans and vegetarians, unlike for folate (vegans: 25.8nmol/L, vegetarians: 21.6nmol/L, p=0.027). Serum B12 concentration <221pmol/L, was found in 14% of all participants. Vegetarians revealed the highest proportion of participants below the RDI of 2 µg/day including supplements (40 vs. 18%, p<0.001). Predictors of higher serum B12 concentrations were average daily supplement use and older age. Folate deficiency (<10 nmol/L) was uncommon overall (<2.5%). The combined indicator cB12 suggested that none of the participants was B12 depleted, however low serum B12 concentration was found in 14% of the participants. Folate concentrations were adequate, indicating adequate folate intake in Norwegian vegans and vegetarians.

• Groufh-Jacobsen, Synne; Bugge, Annechen Bahr; Morseth, Marianne S.; Pedersen, Julia Tsuruta & Henjum, Sigrun (2022). Dietary Habits and Self-Reported Health Measures Among Norwegian Adults Adhering to Plant-Based Diets. Frontiers in Nutrition. 9(9). doi: 10.3389/fnut.2022.813482. Full text in Research Archive Show summary

  Background: As plant-based diets is increasing, we aimed to investigate dietary habits, dietary motivation and self-reported health of Norwegian adults who adhere to different types of plant-based diets. Methods: In 2020, 808 subjects (530 women and 278 men) participated in an online survey, including vegans (8%), lacto-ovo vegetarians (16%), pescatarians (23%), and flexitarians (53%). Results: Half of the participants reported to consume fruits daily, three quarters consumed vegetables daily, and one quarter consumed whole grain products daily. Half of the participants reported weekly consumption of sweets and salted snacks, and 10% reported daily consumption of sugary drinks. Daily consumption of milk and dairy substitutes were reported by vegans (49%), lacto-ovo vegetarians (33%), pescatarians (32%), and flexitarians (25%). Daily consumption of meat replacement products was reported by vegans (3%), lacto-ovo vegetarians (5%), pescatarians (2%). Reported supplement use was highest among vegans (62%) and lowest among flexitarians (28%). Dietary motivations were driven by environmental (71%), health (64%), and animal welfare (49%) concerns, across all dietary groups. 75% reported their self-perceived health to be good or very good. Conclusion: We found that Norwegian adults adhering to plant-based diets consumed less fruit, vegetables, and whole grain products, together with more sugar than recommended in the Norwegian dietary guidelines. The participants reported their self-perceived health to be good or very good.

• Henjum, Sigrun; Groufh-Jacobsen, Synne; Stea, Tonje Holte; Tonheim, Live Edvardsen & Almendingen, Kari (2021). Iron Status of Vegans, Vegetarians and Pescatarians in Norway. Biomolecules. 11(3). doi: 10.3390/biom11030454. Full text in Research Archive Show summary

  Abstract: Although plant-based diets provide well-established physical and environmental health benefits, omitting meat or meat products has also been associated with a risk of being deficient in specific nutrients, such as iron. As data on the iron status among Norwegian vegans, vegetarians and pescatarians are lacking, the present study aimed to assess iron status in these groups of healthy adults. Blood markers for iron status were measured in 191 participants (18–60 years old) comprising 106 vegans, 54 vegetarians and 31 pescatarians: serum-ferritin (S-Fe), serum-iron (S-Iron) and serum-total iron binding capacity (S-TIBC). Serum-transferrin-saturation (S-TSAT) was estimated (S-Iron/S-TIBC × 100). The median concentration of blood markers for iron status were within the normal range with no difference between the different dietary practices. In total, 9% reported iron supplement use the last 24 h. S-Fe concentrations below reference (<15 μg/L) were found in 8% of the participating women, of which one participant reported iron supplement use. In multiple regression analysis, duration of adherence to dietary practices and the female gender were found to be the strongest predictors for decreased S-Fe concentration. In conclusion, although the participants were eating a plant-based diet, the majority had sufficient iron status. Female vegans and vegetarians of reproductive age are at risk of low iron status and should have their iron status monitored.

• Henjum, Sigrun; Groufh-Jacobsen, Synne; Aakre, Inger & Terragni, Laura (2021). Life-course perspectives of milk consumption among young Norwegian women and their knowledge of milk as a source of iodine: a qualitative study. Food & Nutrition Research (FNR). ISSN 1654-6628. 65. doi: 10.29219/fnr.v65.7758. Full text in Research Archive Show summary

  Mild to moderate iodine deficiency has been found among young Norwegian women of reproductive age. In Norway, cow’s milk is the main source of iodine; however, milk consumption is decreasing, particularly among young women. This study aimed to investigate milk consumption practices in young Norwegian women and their attitudes toward milk consumption from childhood to young adulthood in a life-course perspective and their knowledge of milk as a source of iodine. Convenience sampling was used to recruit 30 bachelor students (women, 18–25 years old) from five different study programs. Interpretative phenomenological analysis (IPA) was used to interpret milk consumption practices from a life-course perspective. Five focus group interviews were conducted using a semistructured interview guide. The transcribed interviews were coded according to emerging themes related to milk consumption practices and turning points. Milk consumption practices were dynamic and changed over time and were influenced by several factors: family traditions, school milk subscription, friends and social media, social acceptance, availability, price, and attitudes toward health and the environment. Young women tend to be in a phase of life in which milk is not part of their food practices. Most of the women were not aware of the consequences of omitting milk from their diet and had limited knowledge of iodine and how to secure adequate dietary iodine intake. Awareness of possible consequences of omitting milk from the diet should be promoted along with information on how to secure adequate iodine intake.

• Bakken, Kjersti Sletten; Aarsland, Tonje Eiane; Groufh-Jacobsen, Synne; Solvik, Beate Stokke; Gjengedal, Elin Lovise Folven & Henjum, Sigrun [Show all 7 contributors for this article] (2021). Adequate urinary iodine concentration among infants in the inland area of Norway. Nutrients. 13(6). doi: 10.3390/nu13061826. Full text in Research Archive Show summary

  Abstract Considering the importance of iodine to support optimal growth and neurological development of the brain and central nervous system, this study aimed to assess and evaluate iodine status in Norwegian infants. We collected data on dietary intake of iodine, iodine knowledge in mothers, and assessed iodine concentration in mother's breast milk and in infant's urine in a cross-sectional study at two public healthcare clinics in the inland area of Norway. In the 130 mother-infant pairs, the estimated infant 24-h median iodine intake was 50 (IQR 31, 78) µg/day. The median infant urinary iodine concentration (UIC) was 146 (IQR 93, 250) µg/L and within the recommended median defined by the World Health Organization for this age group. Weaned infants had a higher UIC [210 (IQR 130, 330) µg/L] than exclusively breastfed infants [130 (IQR 78, 210) µg/L] and partially breastfed infants [135 (IQR 89, 250) µg/L], which suggest that the dietary data obtained in this study did not capture the accurate iodine intake of the included infants. The iodine status of infants in the inland area of Norway seemed adequate. Weaned infants had higher UIC compared to breastfed infants, suggesting early access and consumption of other sources of iodine in addition to breast milk. Keywords: Norway; UIC; infants; inland area; iodine; iodine intake; knowledge; urinary iodine concentration.

• Groufh-Jacobsen, Synne; Mosand, Lise Mette; Oma, Ingvild; Bakken, Kjersti Sletten; Solvik, Beate Stokke & Gjengedal, Elin Lovise Folven [Show all 9 contributors for this article] (2020). Mild to Moderate Iodine Deficiency and Inadequate Iodine Intake in Lactating Women in the Inland Area of Norway. Nutrients. 12(3). doi: 10.3390/nu12030630. Full text in Research Archive Show summary

  Breastfed infants are dependent on an adequate supply of iodine in human milk for the production of thyroid hormones, necessary for development of the brain. Despite the importance of iodine for infant health, data on Norwegian lactating women are scarce. We measured iodine intake and evaluated iodine status and iodine knowledge among lactating women. From October to December 2018, 133 mother–infant pairs were recruited in a cross-sectional study through two public health care centers in Lillehammer and Gjøvik. Each of the women provided two human milk specimens, which were pooled, and one urine sample for analysis of iodine concentration. We used 24-h dietary recall and food frequency questionnaire (FFQ) to estimate short-term and habitual iodine intake from food and supplements. The median (P25, P75) human milk iodine concentration (HMIC) was 71 (45, 127) µg/L—of which, 66% had HMIC <100 µg/L. The median (P25, P75) urinary iodine concentration (UIC) was 80 µg/L (52, 141). The mean (± SD) 24-h iodine intake and habitual intake was 78 ± 79 µg/day and 75 ± 73 µg/day, respectively. In conclusion, this study confirms inadequate iodine intake and insufficient iodine status among lactating women in the inland area of Norway and medium knowledge awareness about iodine.

• Bakken, Kjersti Sletten; Oma, Ingvild; Groufh-Jacobsen, Synne; Solvik, Beate Stokke; Mosand, Lise Mette & Langfjord, Mina Marthinsen [Show all 9 contributors for this article] (2020). The Reliability of Iodine Concentration in Diaper-Retrieved Infant Urine Using Urine Collection Pads, and in Their Mothers' Breastmilk. Biomolecules. 10(2). doi: 10.3390/biom10020295. Full text in Research Archive Show summary

  Mild to moderate iodine deficiency is common among women of childbearing age. Data on iodine status in infants are sparse, partly due to the challenges in collecting urine. Urinary iodine concentration (UIC) is considered a good marker for recent dietary iodine intake and status in populations. The aim of this study was to investigate the reliability of iodine concentration measured in two spot-samples from the same day of diaper-retrieved infant urine and in their mothers’ breastmilk. We collected urine and breastmilk from a sample of 27 infants and 25 mothers participating in a cross-sectional study at two public healthcare clinics in Norway. The reliability of iodine concentration was assessed by calculating the intraclass correlation coefficients (ICC) and the coefficient of variation (CV). The ICC for infants’ urine was 0.64 (95% confidence interval (CI) 0.36–0.82), while the ICC for breastmilk was 0.83 (95% CI 0.65–0.92) Similarly, the intraindividual CV for UIC was 0.25 and 0.14 for breastmilk iodine concentration (BIC). Compared to standard methods of collecting urine for measuring iodine concentration, the diaper-pad collection method does not substantially affect the reliability of the measurements.

• Groufh-Jacobsen, Synne; Hess, Sonja; Aakre, Inger; Gjengedal, Elin Lovise Folven; Pettersen, Kristina Blandhoel & Henjum, Sigrun (2020). Vegans, Vegetarians and Pescatarians Are at Risk of Iodine Deficiency in Norway. Nutrients. 12(11). doi: 10.3390/nu12113555. Full text in Research Archive Show summary

  Low iodine intakes have been documented in different population groups in Norway. We aimed to assess iodine status, dietary intake, supplement and macroalgae use, and iodine knowledge in vegans, vegetarians and pescatarians. In this study, 115 vegans, 55 vegetarians and 35 pescatarians from the Oslo region of Norway, aged 18–60 years, participated. A spot urine sample was collected along with a dietary assessment of iodine intake, supplement and macroalgae use. The median urinary iodine concentration (MUIC) in vegans was 43 µg/L (moderate iodine deficiency), in vegetarians 67 µg/L and in pescatarians 96 µg/L (mild iodine deficiency). In multiple linear regression analysis, use of iodine supplements was one of the strongest predictors of UIC. About half of the participants had median 24-h iodine intakes below estimated average requirement (EAR) of 100 µg/day. Fifty percent had low knowledge score, while 27% had very low knowledge score. Vegans, vegetarians and possibly pescatarians in Norway, are unable to reach the recommended iodine intake merely from food and are dependent on iodine supplements. There is an urgent need for dietary guidance targeting vegans, vegetarians and pescatarians to avoid inadequate iodine intake in non-supplement users, as well as avoiding excess iodine intake in macroalgae users. View Full-Text

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• Groufh-Jacobsen, Synne; Brantsæter, Anne Lise; Andersson, Maria & Henjum, Sigrun (2024). Iodine status in two-year-old children and women of childbearing age – Results from a national monitoring study in Norway in 2022–23. Norsk tidsskrift for ernæring (NTFE). ISSN 1503-5034. doi: 10.18261/ntfe.22.5.89. Full text in Research Archive
• Mulkerrins, Isabelle; Medin, Anine Christine; Groufh-Jacobsen, Synne; Margerison, Claire & Larsson, Christel (2024). Micronutrient adequacy among youth adhering to vegan, lacto-ovo-vegetarian, pescatarian and omnivorous diets in Sweden. Full text in Research Archive
• Groufh-Jacobsen, Synne (2023). Unge kan for lite om sunt kosthold. [Internet]. NRK. Full text in Research Archive Show summary

  Ny forskning viser at unge nordmenn har for lite kunnskap om sunt kosthold. Mange sliter med å lese næringsinnhold, forstå merkeordninger og ta gode valg i butikken. Unge får mye informasjon om kosthold fra forskjellige kilder, noe som kan skape forvirring. Forskningen viser at de som vet mest har best kosthold. Unge som ikke har kuttet ut store matvaregrupper, har minst kunnskap og dårligst kvalitet på maten.

• Groufh-Jacobsen, Synne (2023). Unge forstår ikke hva maten inneholder, og kjøttspisere kan minst. [Internet]. forskning.no. Full text in Research Archive
• Groufh-Jacobsen, Synne (2023). Unge kan for lite om sunt kosthold. [TV]. NRK, Helgemorgen. Full text in Research Archive
• Groufh-Jacobsen, Synne (2023). Kor sunt er eigentleg vegetarisk «kjøt»? [Journal]. nationen.no. Full text in Research Archive Show summary

  Nationen spurt eit par ekspertar om å samanlikne eit knippe kjøtprodukt og deira vegetariske erstatningar. "Synne Groufh-Jacobsen, doktorgradsstipendiat i ernæring hjå Universitetet i Agder, er ikkje like krass som Svihus. Ho er først og fremst klar på at det ikkje er nok dokumentasjon til å seie noko om helseeffekten av å velje plantebaserte burgarar eller pølser, framfor kjøtprodukt." "Groufh-Jacobsen summerer opp med å presisere at det er ønskeleg at vi et mindre kjøt, men også viktig å lese næringsdeklarasjonen, då innhaldet i dei ulike vegetar alternativa varierer svært mykje."

• Groufh-Jacobsen, Synne (2023). Unge vet ikke nok om sunn mat. [Internet]. https://www.uia.no/nyheter/unge-vet-ikke-nok-om-sunn-mat. Full text in Research Archive
• Groufh-Jacobsen, Synne (2023). Bærekraftig plantebasert kosthold blant unge. Full text in Research Archive
• Valand, Ida Ulrikke & Groufh-Jacobsen, Synne (2023). Skills for life-podden, episode 6: VeggiSkills og vegetarmat. [Internet]. Spotify, Google Podcasts, Apple Podcasts. Full text in Research Archive Show summary

  Doktorgradsstipendiat Synne Groufh-Jacobsen forteller om VeggiSkills-prosjektet samt fordeler og ulemper med å spise plantebasert!

• Groufh-Jacobsen, Synne; Larsson, Christel; Margerison, Claire; Mulkerrins, Isabelle; Aune, Dagfinn & Medin, Anine Christine (2023). Dietary intake and status of B12, iron and iodine in young vegans, lacto-ovo vegetarians, pescatarians, flexitarians and omnivores. Full text in Research Archive
• Mulkerrins, Isabelle; Medin, Anine Christine; Groufh-Jacobsen, Synne; Margerison, Claire & Larsson, Christel (2023). Agreement between web-based self-administered and interviewer-administered 24-hour recall in Swedish youth. Full text in Research Archive
• Groufh-Jacobsen, Synne (2023). Study explores the knowledge and eating habits of young people with various plant-based diets. [Internet]. https://www.news-medical.net/news/20231212/Study-explores-th. Full text in Research Archive
• Groufh-Jacobsen, Synne (2023). Unge kan ikke nok om sunt kosthold. [Radio]. Sørlandssendinga. Full text in Research Archive
• Groufh-Jacobsen, Synne (2023). Young people lack knowledge about what food contains, and meat eaters know the least. [Internet]. https://partner.sciencenorway.no/adolescents-food-and-nutrit. Full text in Research Archive
• Groufh-Jacobsen, Synne (2022). The 5th Nordic Iodine seminar. Full text in Research Archive Show summary

  Groufh-Jacobsen presented about iodine and plant-based diets and presented her ongoing PhD-project.

• Groufh-Jacobsen, Synne (2022). Nytt innen ernæringsforskning - NTFE-konferansen 2022. Full text in Research Archive Show summary

  Holdt et kort innsalg innen nytt innen ernæringsforskning.

• Groufh-Jacobsen, Synne (2022). Norsk forsker: Vegetarianere spiser for lite frukt og grønt. [Internet]. Nettavisen. Full text in Research Archive
• Groufh-Jacobsen, Synne (2022). Vegetarianarar et ikkje nok frukt og grønt. [Internet]. Nyheter fra Universitetet i Agder. Full text in Research Archive
• Groufh-Jacobsen, Synne (2022). Ny studie: Vegetarianere spiser ikke nok frukt og grønt. [Internet]. NRK.no. Full text in Research Archive
• Groufh-Jacobsen, Synne (2022). Ny studie: Vegetarianere spiser ikke nok frukt og grønt. [Radio]. NRKP1 Sørlandet. Full text in Research Archive
• Groufh-Jacobsen, Synne (2022). Derfor forsker hun på unge vegetarianere i Agder. [Journal]. Fædrelandsvennen. Full text in Research Archive
• Groufh-Jacobsen, Synne (2022). Vegetarianarar et ikkje nok frukt. [Internet]. forskning.no. Full text in Research Archive
• Groufh-Jacobsen, Synne (2022). Vegetarianere spiser ikke nok frukt og grønt. [Radio]. P4. Full text in Research Archive
• Groufh-Jacobsen, Synne (2025). Dietary intake, nutritional status, and food literacy competencies among Norwegian youth following plantbased and omnivore diets. Universitetet i Agder. ISSN 9788284272627. Full text in Research Archive Show summary

  Background: Predominantly plant-based diets offer numerous health benefits, such as reducing the risk of non-communicable diseases. However, poorly planned plant-based diets may pose potential dietary risks, particularly concerning for vulnerable populations, such as youth. The energy and nutrient requirements of youth are increased due to rapid physical growth and cognitive development. Inadequate intake of essential nutrients during this critical life phase can therefore have serious long-term health consequences. At the same time, the youth period represents a transition from dependence of childhood to adulthood independence. During this period, youth gain greater responsibility over their food choices. Therefore, it is of importance for youth to be equipped with the needed food literacy competencies, for them to be able to navigate today’s food environment, and to make health promoting food choices. Particularly, if omitting several food groups from their diet, such as restrictive plant-based diets. In Nordic countries, studies on dietary intake and nutritional status among youth following plant-based diets were last conducted for more than 20 years ago. Currently, data are lacking on this demographic in Norway, highlighting the need for updated research. In addition, data on food literacy among youth following plant-based diets are absent.

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