Sustainability is a key principle in natural resource management, and it involves operational efficiency, minimisation of environmental impact and socio-economic considerations; all of which are interdependent. It has become increasingly obvious that continued reliance on fossil fuel energy resources is unsustainable, owing to both depleting world reserves and the green house gas emissions associated with their use. Therefore, there are vigorous research initiatives aimed at developing alternative renewable and potentially carbon neutral solid, liquid and gaseous biofuels as alternative energy resources. However, alternate energy resources akin to first generation biofuels derived from terrestrial crops such as sugarcane, sugar beet, maize and rapeseed place an enormous strain on world food markets, contribute to water shortages and precipitate the destruction of the world's forests. Second generation biofuels derived from lignocellulosic agriculture and forest residues and from non-food crop feedstocks address some of the above problems; however there is concern over competing land use or required land use changes. Therefore, based on current knowledge and technology projections, third generation biofuels specifically derived from microalgae are considered to be a technically viable alternative energy resource that is devoid of the major drawbacks associated with first and second generation biofuels. Microalgae are photosynthetic microorganisms with simple growing requirements (light, sugars, CO 2 , N, P, and K) that can produce lipids, proteins and carbohydrates in large amounts over short periods of time. These products can be processed into both biofuels and valuable co-products. This study reviewed the technologies underpinning microalgae-to-biofuels systems, focusing on the biomass production, harvesting, conversion technologies, and the extraction of useful co-products. It also reviewed the synergistic coupling of microalgae propagation with carbon sequestration and wastewater treatment potential for mitigation of environmental impacts associated with energy conversion and utilisation. It was found that, whereas there are outstanding issues related to photosynthetic efficiencies and biomass output, microalgae-derived biofuels could progressively substitute a significant proportion of the fossil fuels required to meet the growing energy demand.

/pdf/biofuels-from-microalgae-a-review-of-technologies-for-1t1wwr5e69.pdf

Biofuels from microalgae—A review of technologies for production, processing, and extractions of biofuels and co-products

Clinical epidemiology of inflammatory bowel disease: incidence, prevalence, and environmental influences

Diet, nutrition and the prevention of chronic diseases : report of a Joint WHO/FAO Expert Consultation

https://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(07)60750-8.pdf

Inflammatory bowel disease: cause and immunobiology

Health Benefits of Fruits and Vegetables

The UK dietary guidelines for cardiovascular disease acknowledge the importance of long-chain omega-3 polyunsaturated fatty acids (PUFA) - a component of fish oils - in reducing heart disease risk. At the time, it was recommended that the average n-3 PUFA intake should be increased from 0.1 to 0.2 g day(-1). However, since the publication of these guidelines, a plethora of evidence relating to the beneficial effects of n-3 PUFAs, in areas other than heart disease, has emerged. The majority of intervention studies, which found associations between various conditions and the intake of fish oils or their derivatives, used n-3 intakes well above the 0.2 g day(-1) recommended by Committee on Medical Aspects of Food Policy (COMA). Furthermore, in 2004, the Food Standards Agency changed its advice on oil-rich fish creating a discrepancy between the levels of n-3 PUFA implied by the new advice and the 1994 COMA guideline. This review will examine published evidence from observational and intervention studies relating to the health effects of n-3 PUFAs, and discuss whether the current UK recommendation for long-chain n-3 PUFA needs to be revisited.

https://www.csuchico.edu/grassfedbeef/research/documents/sources/Ruxton%20Omega3%20review.pdf

The health benefits of omega-3 polyunsaturated fatty acids: a review of the evidence

The UK dietary guidelines for cardiovascular disease acknowledge the importance of long-chain omega-3 polyunsaturated fatty acids (PUFA) - a component of fish oils - in reducing heart disease risk. At the time, it was recommended that the average n-3 PUFA intake should be increased from 0.1 to 0.2 g day -1 . However, since the publication of these guidelines, a plethora of evidence relating to the beneficial effects of n-3 PUFAs, in areas other than heart disease, has emerged. The majority of intervention studies, which found associations between various conditions and the intake of fish oils or their derivatives, used n-3 intakes well above the 0.2 g day -1 recommended by Committee on Medical Aspects of Food Policy (COMA). Furthermore, in 2004, the Food Standards Agency changed its advice on oil-rich fish creating a discrepancy between the levels of n-3 PUFA implied by the new advice and the 1994 COMA guideline. This review will examine published evidence from observational and intervention studies relating to the health effects of n-3 PUFAs, and discuss whether the current UK recommendation for long-chain n-3 PUFA needs to be revisited.

The health benefits of omega-3 polyunsaturated fatty acids: a review of the evidence. Commentary

A considerable literature has been published on the health benefits of fish, oil-rich fish and fish oils and their constituent long-chain (LC) n-3 PUFA. Evidence from epidemiological studies highlights the cardioprotective attributes of diets rich in fish, especially oil-rich fish. Data from intervention trials are consistent in suggesting that LC n-3 PUFA lower the risk of CVD, probably by the multiple mechanisms of lowering serum triacylglycerols, improving the LDL:HDL ratio, anti-arrhythmic effects on heart muscle, improved plaque stability, anti-thrombotic effects and reduced endothelial activation. Research indicates LC n-3 PUFA provision has an impact during development, and there is preliminary evidence that docosahexaenoic acid supplementation during pregnancy could optimise brain and retina development in the infant. LC n-3 PUFA are also postulated to ameliorate behavioural and mental health disturbances such as depression, schizophrenia, dementia and attention deficit hyperactivity disorder. However, despite some positive evidence in each of these areas, use of LC n-3 PUFA in these conditions remains at the experimental stage. In the case of immune function, there is little doubt that LC n-3 PUFA have a positive effect. Although intervention trials in rheumatoid arthritis show strong evidence of benefit, evidence for efficacy in other inflammatory conditions, including Crohn's disease, ulcerative colitis, psoriasis, lupus, multiple sclerosis, cystic fibrosis and asthma, is inconsistent or inadequate. More promising evidence in some conditions may come from studies which attempt to modify the fetal environment using LC n-3 PUFA supplementation during pregnancy.

/pdf/the-impact-of-long-chain-n-3-polyunsaturated-fatty-acids-on-4628dag5zc.pdf

The impact of long-chain n-3 polyunsaturated fatty acids on human health

To consider whether consumption of black tea has a positive or negative impact on health. Databases were searched for relevant epidemiological and clinical studies published between 1990 and 2004. Clear evidence was found for coronary heart disease (CHD), where an intake of ⩾3 cups per day related to risk reduction. The mechanism could involve the antioxidant action of tea polyphenols. While experimental models have suggested that flavonoids attenuated cancer risk, epidemiological studies failed to demonstrate a clear effect for tea, although there is moderate evidence for a slightly positive or no effect of black tea consumption on colorectal cancer. Studies on cancer were limited by sample sizes and insufficient control of confounders. There is moderate evidence suggestive of a positive effect of black tea consumption on bone mineral density although studies were few. There is little evidence to support the effect of tea on dental plaque inhibition but evidence to support the contribution of tea to fluoride intakes and thus theoretical protection against caries. There was no credible evidence that black tea (in amounts typically consumed) was harmful. Normal hydration was consistent with tea consumption when the caffeine content was <250 mg per cup. A moderate caffeine intake from tea appeared to improve mental performance, although sample sizes were small. There was no evidence that iron status could be harmed by tea drinking unless populations were already at risk from anaemia. There was sufficient evidence to show risk reduction for CHD at intakes of ⩾3 cups per day and for improved antioxidant status at intakes of one to six cups per day. A maximum intake of eight cups per day would minimise any risk relating to excess caffeine consumption. Black tea generally had a positive effect on health. The Tea Council. The authors confirm that the sponsors played no role in the writing of this review.

http://www.nutricion.sochipe.cl/subidos/noticias2/docs/propiedades_te.pdf

Black tea--helpful or harmful? A review of the evidence.

The present paper reviews the literature on breakfast to consider reported association between breakfast and nutritional, physiological and biochemical variables. The contribution of breakfast to achieving nutrition targets for fat, carbohydrate and dietary fibre intakes is also examined as are the potential effects of fortified breakfast cereals on intakes of micronutrients and nutritional status. Breakfast consumption, particularly if the meal includes a breakfast cereal, is associated with lower intakes of fat and higher intakes of carbohydrate, dietary fibre and certain micronutrients. These findings may be relevant to population groups which could be at risk from low intakes of certain micronutrients, but further clarification of benefit is needed from studies of nutritional status. Associations between breakfast consumption and lower cholesterol levels have been reported, while lower body weights have been seen amongst breakfast eaters. It is concluded that breakfast consumption is a marker for an appropriate dietary pattern in terms of both macro- and micronutrients, particularly if breakfast cereals are included in the meal.

/pdf/breakfast-a-review-of-associations-with-measures-of-dietary-44e3ok8bje.pdf

C. H. S. Ruxton

Papers

The health benefits of omega-3 polyunsaturated fatty acids: a review of the evidence

The health benefits of omega-3 polyunsaturated fatty acids: a review of the evidence. Commentary

The impact of long-chain n-3 polyunsaturated fatty acids on human health

Black tea--helpful or harmful? A review of the evidence.

Breakfast: a review of associations with measures of dietary intake, physiology and biochemistry.