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Metabolomics has been utilised in epidemiological studies to investigate biomarkers of nutritional status and metabolism in relation to non-communicable diseases. However, little is known about the effect of prandial status on several biomarker concentrations. Therefore, the aim of this intervention study was to investigate the effect of a standardised breakfast meal followed by food abstinence for 24 h on serum concentrations of amino acids, one-carbon metabolites and B-vitamin biomarkers. Thirty-four healthy subjects (eighteen males and sixteen females) aged 20–30 years were served a breakfast meal (∼500 kcal) after which they consumed only water for 24 h. Blood samples were drawn before and at thirteen standardised timepoints after the meal. Circulating concentrations of most amino acids and metabolites linked to one-carbon metabolism peaked within the first 3 h after the meal. The branched-chain amino acids steadily increased from 6 or 8 hours after the meal, while proline decreased in the same period. Homocysteine and cysteine concentrations immediately decreased after the meal but steadily increased from 3 and 4 hours until 24 h. FMN and riboflavin fluctuated immediately after the meal but increased from 6 h, while folate increased immediately after the meal and remained elevated during the 24 h. Our findings indicate that accurate reporting of time since last meal is crucial when investigating concentrations of certain amino acids and one-carbon metabolites. Our results suggest a need for caution when interpretating studies, which utilise such biomarkers, but do not strictly control for time since the last meal. [ABSTRACT FROM AUTHOR]

Vitamin B12 (cobalamin) is essential for normal metabolic function, and even moderate deficiency of this vitamin has negative health effects. Vitamin B12 is found in animal foods, and as vegetarian diets are increasingly popular in Western countries, one might expect a higher prevalence of vitamin B12 deficiency in the Nordic population. Setting recommendations for vitamin B12 intake has proven to be difficult, as uptake of vitamin B12 varies substantially, the clinical deficiency symptoms are often diffuse, and there is no clear agreement on the decision limits for vitamin B12 deficiency. Vitamin B12 deficiency is reported to be particularly common among pregnant women and infants, despite the fact that less than 1% of Norwegian pregnant women have a cobalamin intake below the Nordic Nutrition Recommendations 2012-recommended level of 2.0 µg/day. In addition, the assumption that breast milk contains sufficient vitamin B12 for optimal health and neurodevelopment during the first 6 months of life does not comply with the high prevalence of insufficient vitamin B12 status in this age group. Recommended intakes of vitamin B12 vary among age groups and must be based on markers of cobalamin status, indicating an optimal intracellular biochemical status, and not merely absence of clinical signs of vitamin B12 deficiency. [ABSTRACT FROM AUTHOR]

Objective: Limiting SFA intake may minimise the risk of CHD. However, such reduction often leads to increased intake of carbohydrates. We aimed to evaluate associations and the interplay of carbohydrate and SFA intake on CHD risk.Design: Prospective cohort study.Setting: We followed participants in the Hordaland Health Study, Norway from 1997-1999 through 2009. Information on carbohydrate and SFA intake was obtained from a FFQ and analysed as continuous and categorical (quartiles) variables. Multivariable Cox regression estimated hazard ratios (HR) and 95 % CI. Theoretical substitution analyses modelled the substitution of carbohydrates with other nutrients. CHD was defined as fatal or non-fatal CHD (ICD9 codes 410-414 and ICD10 codes I20-I25).Participants: 2995 men and women, aged 46-49 years.Results: Adjusting for age, sex, energy intake, physical activity and smoking, SFA was associated with lower risk (HRQ4 v. Q1 0·44, 95 % CI 0·26, 0·76, Ptrend = 0·002). For carbohydrates, the opposite pattern was observed (HRQ4 v. Q1 2·10, 95 % CI 1·22, 3·63, Ptrend = 0·003). SFA from cheese was associated with lower CHD risk (HRQ4 v. Q1 0·44, 95 % CI 0·24, 0·83, Ptrend = 0·006), while there were no associations between SFA from other food items and CHD. A 5 E% substitution of carbohydrates with total fat, but not SFA, was associated with lower CHD risk (HR 0·75, 95 % CI 0·62, 0·90).Conclusions: Higher intake of predominantly high glycaemic carbohydrates and lower intake of SFA, specifically lower intake from cheese, were associated with higher CHD risk. Substituting carbohydrates with total fat, but not SFA, was associated with significantly lower risk of CHD. [ABSTRACT FROM AUTHOR]

To improve the interpretation and utilisation of blood lipids, ketones and acylcarnitine concentrations as biomarkers in clinical assessments, more information is needed on their dynamic alterations in response to dietary intake and fasting. The aim of this intervention study was to characterise the changes in serum lipid, ketone and acylcarnitine concentrations 24 h after a standardised breakfast meal. Thirty-four healthy subjects (eighteen males and sixteen females) aged 20-30 years were served a breakfast meal (∼500 kcal, 36 E% fat, 46 E% carbohydrates, 16 E% protein, 2E% fibre), after which they consumed only water for 24 h. Blood samples were drawn before and at thirteen standardised timepoints after the meal. Metabolite concentrations were plotted as a function of time since the completion of the breakfast meal. Results demonstrated that concentrations of HDL-cholesterol and LDL-cholesterol decreased until ∼2 h (-4 % for both), while TAG concentrations peaked at 3 h (+27 %). Acetoacetate and β -hydroxybutyrate were highest 24 h after the meal (+433 and +633 %, respectively). Acetylcarnitine, butyrylcarnitine, hexanoylcarnitine, octanoylcarnitine, decanoylcarnitine and dodecanoylcarnitine reached the lowest values at 60 min (decreases ranging from -47 to -70 %), before increasing and peaking at 24 h after the meal (increases ranging from +86 to +120 %). Our findings suggest that distinguishing between fasting and non-fasting blood samples falls short of capturing the dynamics in lipid, ketone, carnitine and acylcarnitine concentrations. To enhance the utility of serum acylcarnitine analyses, we strongly recommend accounting for the specific time since the last meal at the time of blood sampling.

Vitamin B 12 (cobalamin) is essential for normal metabolic function, and even moderate deficiency of this vitamin has negative health effects. Vitamin B 12 is found in animal foods, and as vegetarian diets are increasingly popular in Western countries, one might expect a higher prevalence of vitamin B 12 deficiency in the Nordic population. Setting recommendations for vitamin B 12 intake has proven to be difficult, as uptake of vitamin B 12 varies substantially, the clinical deficiency symptoms are often diffuse, and there is no clear agreement on the decision limits for vitamin B 12 deficiency. Vitamin B 12 deficiency is reported to be particularly common among pregnant women and infants, despite the fact that less than 1% of Norwegian pregnant women have a cobalamin intake below the Nordic Nutrition Recommendations 2012-recommended level of 2.0 µg/day. In addition, the assumption that breast milk contains sufficient vitamin B 12 for optimal health and neurodevelopment during the first 6 months of life does not comply with the high prevalence of insufficient vitamin B 12 status in this age group. Recommended intakes of vitamin B 12 vary among age groups and must be based on markers of cobalamin status, indicating an optimal intracellular biochemical status, and not merely absence of clinical signs of vitamin B 12 deficiency., Competing Interests: The authors have not received any funding or benefits from industry or elsewhere to conduct this study., (© 2023 Monsen and Lysne.)

Aims: Blockade of β-adrenoceptors reduces sympathetic nervous system activity and improves survival in patients with heart failure with reduced left ventricular ejection fraction (HFrEF); however, any improvement in longevity among patients with coronary heart disease (CHD) but without HFrEF remains uncertain. Vitamin A has been linked to the activation of tyrosine hydroxylase, the rate-limiting enzyme in the catecholamine synthesis pathway. We investigated if vitamin A status modified the association of β-blocker use with the risk of all-cause mortality., Methods and Results: A total of 4118 patients undergoing elective coronary angiography for suspected stable angina pectoris, of whom the majority had normal left ventricular ejection fraction (LVEF) were studied. Hazard ratios (HRs) of all-cause mortality comparing treatment vs. non-treatment of β-blockers according to the tertiles of serum vitamin A were explored in Cox proportional hazards regression models. During a median follow-up of 10.3 years, 897 patients (21.8%) died. The overall LVEF was 65% and 283 (6.9%) had anamnestic HF. After multivariable adjustments for traditional risk factors, medical history, and drug therapies of cardiovascular disease, β-blocker treatment was inversely associated with the risk of all-cause mortality [HR : 0.84; 95% CI (confidence interval), 0.72-0.97]. However, the inverse association was generally stronger among patients in the upper serum vitamin A tertile (HR :0.66; 95% CI, 0.50-0.86; Pinteraction = 0.012), which remained present after excluding patients with LVEF < 40%., Conclusion: In patients with suspected CHD, β-blocker treatment was associated with improved survival primarily among patients with high serum vitamin A levels., (© The Author(s) 2021. Published by Oxford University Press on behalf of the European Society of Cardiology.)