Home > Newsletters > Daily: Love or hate Earth Hour? > Daily Dose: This is why your vanilla or cinnamon flavoured e-cigarette is toxic > Health-in-Motion 30 May 2017 When trying to lose weight, should you eat or fast before exercising? When trying to lose weight, should you eat or fast before exercising? That’s one of the questions British researchers tried to answer in a recent study by looking at the expression of genes in the fat tissue of a group of overweight males. The expression of the genes PDK4 and HSL increased when the test subjects didn’t eat before exercising, suggesting that energy from stored fat was used to power the physical exercise, potentially leading to weight loss. The opposite was the case when the men ate before exercising. 0 More: Daily Dose: This is why your vanilla or cinnamon flavoured e-cigarette is toxicHealth-in-Motion advertisement Other news Medical WATCH: 5 science-backed hangover cures Mental health WATCH: 6 ways to battle Sunday sadness Sex Scientists have worked for decades to develop a vaccine for herpes - now they've found a crucial clue in containing the virus Medical Why are cardiac arrests more deadly on weekends? News #NHIPublicHearings: Vhembe residents weigh in on the bill Medical Windy, humid days could bring more pain Live healthier Lifestyle » E-cigarettes: Here are five things to know E-cigarettes have become hugely popular in the past decade, but a rash of vaping-linked deaths and illnesses in the US is feeding caution about a product that's already banned in some places. Allergy » Ditch the itch: Researchers find new drug to fight hives A new drug works by targeting an immune system antibody called immunoglobulin E, which is responsible for the allergic reaction that causes hives.