prevalence of inadequate intakes and associated health outcomes

© 2022 The Authors. Annals of the New York Academy of Sciences published by Wiley Periodicals LLC on behalf of New York Academy of Sciences.Dietary calcium deficiency is considered to be widespread globally, with published estimates suggesting that approximately half of the world's population has inadequate access to dietary calcium. Calcium is essential for bone health, but inadequate intakes have also been linked to other health outcomes, including pregnancy complications, cancers, and cardiovascular disease. Populations in low- and middle-income countries (LMICs) are at greatest risk of low calcium intakes, although many individuals in high-income countries (HICs) also do not meet recommendations. Paradoxically, many LMICs with lower calcium intakes show lower rates of osteoporotic fracture as compared with HICs, though data are sparse. Calcium intake recommendations vary across agencies and may need to be customized based on other dietary factors, health-related behaviors, or the risk of calcium-related health outcomes. The lack of standard methods to assess the calcium status of an individual or population has challenged efforts to estimate the prevalence of calcium deficiency and the global burden of related adverse health consequences. This paper aims to consolidate available evidence related to the global prevalence of inadequate calcium intakes and associated health outcomes, with the goal of providing a foundation for developing policies and population-level interventions to safely improve calcium intake and status where necessary.publishersversionepub_ahead_of_prin

current evidence and programmatic considerations

Funding Information: We are thankful to Ann Prentice for her critical review of the section ?Concerns in populations with low calcium intake.? The convenings of the Calcium Task Force and the development of this paper and its open access were supported by funding from The Children's Investment Fund Foundation to the Nutrition Science Program of the New York Academy of Sciences. Publisher Copyright: © 2022 The Authors. Annals of the New York Academy of Sciences published by Wiley Periodicals LLC on behalf of New York Academy of Sciences.Most low- and middle-income countries present suboptimal intakes of calcium during pregnancy and high rates of mortality due to maternal hypertensive disorders. Calcium supplementation during pregnancy is known to reduce the risk of these disorders and associated complications, including preeclampsia, maternal morbidity, and preterm birth, and is, therefore, a recommended intervention for pregnant women in populations with low dietary calcium intake (e.g., where ≥25% of individuals in the population have intakes less than 800 mg calcium/day). However, this intervention is not widely implemented in part due to cost and logistical issues related to the large dose and burdensome dosing schedule (three to four 500-mg doses/day). WHO recommends 1.5–2 g/day but limited evidence suggests that less than 1 g/day may be sufficient and ongoing trials with low-dose calcium supplementation (500 mg/day) may point a path toward simplifying supplementation regimens. Calcium carbonate is likely to be the most cost-effective choice, and it is not necessary to counsel women to take calcium supplements separately from iron-containing supplements. In populations at highest risk for preeclampsia, a combination of calcium supplementation and food-based approaches, such as food fortification with calcium, may be required to improve calcium intakes before pregnancy and in early gestation.publishersversionpublishe

Navigating of microtubule obstacles by ensembles of dynein

Dynein is a microtubule-associated motor protein that facilitates the transport of essential cargos within the cell. Given the sheer size difference between this motor and its many cargos, dynein often works together in teams with other motor proteins to accomplish their transporting tasks. Failure of this transport system results in neurological diseases. To understand and contextualize how these malfunctions occur, we are investigating the fundamental biophysical mechanisms that drive intracellular cargo transport. To do this, we have turned to an in vitro system using DNA origami as a highly controllable synthetic cargo structure that allows us to construct and model how multiple dynein motor proteins work in a concerted effort to transport cargos. To push this experimental system toward greater biological relevance, we investigated motor ensemble transport in the presence of obstacles along the microtubule surface. Additionally, to mirror the crowded cytoskeletal intracellular environment, we performed microtubule crossing experiments to probe how precisely organized teams of motor proteins navigate through the dense microtubule network