According to a recent study, obesity increases the risk of dying of Covid-19 by nearly 50%. Governments around the world are now hoping to encourage their citizens to lose weight. But with so much complex and often contradictory diet advice, as well as endless food fads, it can be hard to know what healthy eating actually looks like.
How many pieces of fruit and vegetables should you eat a day? Will cutting out carbs help you lose weight? Is breakfast really the most important meal of the day? Speaking to Tim Spector, professor of genetic epidemiology at King’s College London about his new book Spoon-Fed, Madeleine Finlay asks why we’re still getting food science wrong, and explores the current scientific evidence on snacking, supplements and calorie labels.
Tim Spector is a Professor of Genetic Epidemiology and Director of the TwinsUK Registry at Kings College, London and has recently been elected to the prestigious Fellowship of the Academy of Medical Sciences. He trained originally in rheumatology and epidemiology. In 1992 he moved into genetic epidemiology and founded the UK Twins Registry, of 13,000 twins, which is the richest collection of genotypic and phenotypic information worldwide. He is past President of the International Society of Twin Studies, directs the European Twin Registry Consortium (Discotwin) and collaborates with over 120 centres worldwide. He has demonstrated the genetic basis of a wide range of common complex traits, many previously thought to be mainly due to ageing and environment. Through genetic association studies (GWAS), his group have found over 500 novel gene loci in over 50 disease areas. He has published over 800 research articles and is ranked as being in the top 1% of the world’s most cited scientists by Thomson-Reuters. He held a prestigious European Research Council senior investigator award in epigenetics and is a NIHR Senior Investigator. His current work focuses on omics and the microbiome and directs the crowdfunded British Gut microbiome project. Together with an international team of leading scientists including researchers from King’s College London, Massachusetts General Hospital, Tufts University, Stanford University and nutritional science company ZOE he is conducting the largest scientific nutrition research project, showing that individual responses to the same foods are unique, even between identical twins. You can find more on https://joinzoe.com/ He is a prolific writer with several popular science books and a regular blog, focusing on genetics, epigenetics and most recently microbiome and diet (The Diet Myth). He is in demand as a public speaker and features regularly in the media.
NEW ENGLAND JOURNAL OF MEDICINE (JULY 23, 2020): A large body of evidence suggests that consumption of caffeinated coffee, the main source of caffeine intake in adults in the United States, does not increase the risk of cardiovascular diseases and cancers. In fact, consumption of 3 to 5 standard cups of coffee daily has been consistently associated with a reduced risk of several chronic diseases.
Coffee and tea have been consumed for hundreds of years and have become an important part of cultural traditions and social life.5 In addition, people use coffee beverages to increase wakefulness and work productivity. The caffeine content of commonly used sources of caffeine is shown in Table 1. For a typical serving, the caffeine content is highest in coffee, energy drinks, and caffeine tablets; intermediate in tea; and lowest in soft drinks. In the United States, 85% of adults consume caffeine daily,6 and average caffeine intake is 135 mg per day, which is equivalent to about 1.5 standard cups of coffee (with a standard cup defined as 8 fluid oz [235 ml]).7 Coffee is the predominant source of caffeine ingested by adults, whereas soft drinks and tea are more important sources of caffeine ingested by adolescents,
Vitamins and minerals, as we all know, are of critical importance to our health. Gone are the days when scurvy(vitamin C) was the scourge of the high seas, and rickets (vitamin D) was common in the children of smoke-filled industrial cities with insufficient sunlight.
We are in a state of such overabundance that many medical authorities feel that vitamin supplementation merely makes our toilets healthier.
Covid 19, with a deficit of prevention and treatment options, has forced a new appreciation of the role of our immune systems in fending off Covid, and future viral plagues that are certain to follow. Optimum Health has never been more important.
A May 4, 2020, British Medical Journal (BMJ) article highlights the role of vitamins C and D, and minerals, especially Zinc, in functioning of our immune systems. Here are several highlights from the article:
- Foods that are naturally abundant in vitamin C such as broccoli (60 mg/100 g), blackcurrants (130 mg/100 g), fortified breakfast cereals (up to 134 mg/100 g) and oranges (37–52 mg/100 g)45 should be made accessible to older individuals who are most in need of their nutritional benefits.
- In the UK 5.5% of men and 4% of women 65 years and over (around 1 in 20) presently have zinc intakes lower than the lower reference nutrient intake (the level below which deficiency could occur).46 The consumption of foods naturally abundant in zinc such as canned crab (5.7 mg/100 g), canned shrimps (3.7 mg/100 g), canned adzuki beans (≈2.3 mg/100 g) and boiled eggs (1.3 mg/100 g) should be encouraged as a supplementation strategy to reinforce immunity.
- Tolerable upper intake levels (ULs) are intake levels which should not be surpassed as toxicity problems could appear.47 For vitamin D a UL of 50 µg/day is advised and for zinc a UL of 25 mg/day is recommended. 47 There is insufficient evidence to establish UL for vitamin C, but available human data suggest that supplemental daily doses of up to about 1 g, in addition to normal dietary intake, are not associated with adverse gastrointestinal effects.47 Not having an adverse effect, however, is not necessarily indicative of a benefit either, and ongoing trials are warranted.
- Among those with established respiratory conditions or pneumonia, specific nutrients such as vitamin C, D or zinc could be considered as potential adjuvants to conventional treatment pathways.
Susceptible people, particularly the old, should use every safe measure to stay well.