Recent advances in wearable sensor technologies offer new opportunities for improving dietary adherence. However, despite their tremendous promise, the potential of wearable chemical sensors for guiding personalized nutrition solutions has not been reported. Herein, we present an epidermal biosensor aimed at following the dynamics of sweat vitamin C after the intake of vitamin C pills and fruit juices. Such skin-worn noninvasive electrochemical detection of sweat vitamin C has been realized by immobilizing the enzyme ascorbate oxidase (AAOx) on flexible printable tattoo electrodes and monitoring changes in the vitamin C level through changes in the reduction current of the oxygen cosubstrate. The flexible vitamin C tattoo patch was fabricated on a polyurethane substrate and combined with a localized iontophoretic sweat stimulation system along with amperometric cathodic detection of the oxygen depletion during the enzymatic reaction. The enzyme biosensor offers a highly selective response compared to the common direct (nonenzymatic) voltammetric measurements, with no effect on electroactive interfering species such as uric acid or acetaminophen. Temporal vitamin C profiles in sweat are demonstrated using different subjects taking varying amounts of commercial vitamin C pills or vitamin C-rich beverages. The dynamic rise and fall of such vitamin C sweat levels is thus demonstrated with no interference from other sweat constituents. Differences in such dynamics among the individual subjects indicate the potential of the epidermal biosensor for personalized nutrition solutions. The flexible tattoo patch displayed mechanical resiliency to multiple stretching and bending deformations. In addition, the AAOx biosensor is shown to be useful as a disposable strip for the rapid in vitro detection of vitamin C in untreated raw saliva and tears following pill or juice intake. These results demonstrate the potential of wearable chemical sensors for noninvasive nutrition status assessments and tracking of nutrient uptake toward detecting and correcting nutritional deficiencies, assessing adherence to vitamin intake, and supporting dietary behavior change.

Supplementation with antioxidant micronutrients is not an effective tool for gastric cancer control in this high-risk population. The results of this trial are consistent with previous findings on the lack of effect of nutritional supplementation on precancerous gastric lesions.

No abstract

The systemic availability of synthetic lycopene from a tablet formulation is comparable to that observed from processed tomatoes (soup from tomato paste) and superior to that from tomato juice. No differences were observed in disposition kinetics of natural and synthetic lycopene. The synthetic lycopene tablet formulation used in this investigation may be of value for future clinical investigations.

Background — Aging is an independent risk factor for the development of cardiovascular disease. Therefore, therapies to delay vascular aging may have enormous medical consequences. In this context, vitamin E is of particular interest, mainly because of its antioxidative properties. Methods and Results — In 3-year-old rats, which are not susceptible to atherosclerosis, vitamin E levels, as measured by reversed-phase high-performance liquid chromatography, were markedly increased both in plasma and in major organs ( P <0.01 to P <0.0001). The highest increase (at least 70-fold) was found in the aortic wall. Conclusions — This unexpected accumulation of vitamin E appears to be a compensatory mechanism that attempts to counterbalance age-associated oxidative stress and that may represent a self-regulatory protective adaptation.

Surveys in high-income countries show that inadequacies and deficiencies can be common for some nutrients, particularly in vulnerable subgroups of the population. Inadequate intakes, high requirements for rapid growth and development, or age- or disease-related impairments in nutrient intake, digestion, absorption, or increased nutrient losses can lead to micronutrient deficiencies. The consequent subclinical conditions are difficult to recognize if not screened for and often go unnoticed. Nutrient deficiencies can be persistent despite primary nutrition interventions that are aimed at improving dietary intakes. Secondary prevention that targets groups at high risk of inadequacy or deficiency, such as in the primary care setting, can be a useful complementary approach to address persistent nutritional gaps. However, this strategy is often underestimated and overlooked as potentially cost-effective means to prevent future health care costs and to improve the health and quality of life of individuals. In this paper, the authors discuss key appraisal criteria to consider when evaluating the benefits and disadvantages of a secondary prevention of nutrient deficiencies through screening.

Background/Aims: Tocotrienols has been shown to inhibit the 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase activity; however, the published animal and human studies yield conflicting results. We investigated the effects of a 4-week dietary supplement of either γ-tocotrienol (86% γ-T3) or a mixture of tocotrienols (29.5% α-T3, 3.3% β-T3, 41.4% γ-T3, 0.1% δ-T3: mix-T3) on the plasma lipid profile in hamsters receiving a high fat diet. Methods: The hamsters were randomized into 7 groups: no treatment, 16 mg/day/kg BW simvastatin, 23, 58, 263 mg/day/kg BW γ-tocotrienol, and 39 or 263 mg/day/kg BW for the mixture of tocotrienols. Plasma lipid levels were measured after 2 and 4 weeks of treatment. Results: In all groups treated with tocotrienol total cholesterol levels were decreased, ranging from 7 to 23% after 2 weeks of treatment and from 7 to 15% after 4 weeks. Low-density lipoprotein plasma levels changed accordingly: a decline of 6–37% after 2 weeks and of 12–32% at the end of the study was observed. After 4 weeks of treatment, total cholesterol and low-density lipoprotein plasma levels were significantly reduced in the 263 mg/day/kg BW mixed tocotrienols and the 58 mg/day/kg BW and 263 mg/day/kg BW γ-tocotrienol groups when compared to the no treatment group. Plasma triglycerides and high-density lipoprotein levels did not change significantly. Conclusion: This study provides further evidence that tocotrienols lower total cholesterol and low density lipoprotein plasma levels in hamsters and that γ-tocotrienol is a more potent agent than a mixture of tocotrienols.

Ageing is an independent risk factor for the development of cardiovascular disease. The ageing process is known to be associated with increased oxidative stress and an increased risk for cardiovascular and other diseases, such as cancer. To delay this process, therapeutic strategies involving the use of naturally occurring antioxidants, such as vitamin A, have gained considerable interest. Therefore, we wanted to investigate in a model of mammalian ageing whether changes in tissue and plasma levels of vitamin A occur with increasing age. This would constitute a prime rationale for its dietary supplementation. Experiments were performed in three different age groups (4-6 months old, 19 months old, 32-35 months old) of F1 (F344 x BN) healthy male rats that were fed a normal diet without any additional supplementation. Vitamin A and carotenoids in plasma and major organs were measured by reverse-phase high-performance liquid chromatography. In 3-year-old rats, vitamin A levels were found to be decreased in plasma (P < 0.0001) as compared with young and middle-aged animals. However, they were markedly increased in the main storage organ (ie, the liver) (P < 0.01-0.0001), and also in the aortic vessel wall. They were undetectable in the heart, irrespective of age. Increased tissue levels of vitamin A, especially in the vasculature, may be part of an age-associated self-regulatory process of adaptation, possibly as a counter-regulation against oxidative tissue damage. Based upon the assumption that in elderly humans, as in our animal model, a similar demand-regulated mechanism may work independently of additional dietary vitamin A supplementation, one may question the strategy of large clinical interventional trials using vitamin A or its derivatives beyond normal dietary intake.