14th June is observed as World Blood Donor Day by WHO to inspire people around the world to donate blood and save lives. If you are planning to donate blood this time then read this before you do.Last time you donated blood did you feel nauseous and faint hearted and were foxed with how your body had reacted? Maybe you did one of the two things wrong: you didn’t fuel up properly in the morning before donating or did not hydrate yourself after donating.DosThere are some simple but essential diet dos and don’ts that one must follow both before and after blood donation.Have Iron-Rich FoodsRemoving red blood cells removes iron stores from your body (iron carries oxygen to your cells), and low iron levels can cause weakness and fatigue, which could lead to fainting or passing out after you donate. Snack on prunes, figs, eggs, liver, tomato juice and other iron rich foods.Have Vitamin C Rich FoodsInclude some vitamin C rich foods too in your diet to ensure better absorption of iron. Eat amla and other citrus fruits.Hydration Is EssentialBiggest cause of fainting and dizziness is a drop in blood pressure and getting in lots of water and juice helps keep the pressure stable.Drink at least eight glasses of liquids in the morning of donation including 3-4 glasses in the two hours before you go.And skip aerated drinks and caffeine completely on the day.Carry Something Sweet AlongAfter the donation it is important to hydrate and refuel a bit with a high sugar snack. So carry something along.World Blood Donor Day: Who Can Donate Blood & How Can They Do So?Drink Plenty of LiquidsDrinking plenty of liquids is also very important just after giving blood, to help replace the fluid you just lost. And continue drinking plenty of liquids for the next 24 to 48 hours to prevent low BP.Have Foods Rich In Folic AcidsFor a few weeks after the donation have foods rich in folic acids it helps to manufacture new red blood cells to help to replace blood cells lost during donation. So stock up on liver, dried beans, asparagus and green leafy vegetables like spinach, orange juice and fortified breads.Eat Food Rich In CarbohydratesAlso eat high quality, high energy carbohydrate foods to help your body turn carbohydrates into energy and effectively fight fatigue.From Amla to Brahmi: Ayurvedic Tips to Control High Blood PressureDon’tsAvoid High Caffeine DrinksTotally avoid high caffeine drinks (carbonated drinks, too much coffee) and alcohol for a day or two after donation as these are diuretics and may cause water loss, thus compounding the problem.Avoid High Fat FoodsAvoid high fat foods as high lipid count in the blood may interfere with some of the tests (for infectious diseases) and make your blood unusable. So no chips, mayonnaise, butter, samosas and oil dripping gravies please.Never Go On An Empty StomachEat a wholesome meal about 2-3 hours before donating to keep your blood sugar stable (and help ward off light heartedness). But don’t eat just before donation, as that might unsettle your stomach a bit and make you nauseous.(The author is a nutritionist, weight management consultant and health writer based in Delhi. She is the author of Don't Diet! 50 Habits of Thin People (Jaico) and Ultimate Grandmother Hacks: 50 Kickass Traditional Habits for a Fitter You (Rupa).