Why the slump happens
A meal made mostly of refined carbohydrate, such as a bagel, a bowl of sweetened cereal or a plate of plain pasta, digests fast. Blood sugar rises quickly, insulin follows, and ninety minutes to two hours later you are foggy, irritable and hunting for something sweet, which starts the cycle again. Protein, fiber and fat all slow that curve. The practical rule is never to eat a carbohydrate alone: put peanut butter on the toast, eat the apple with a handful of nuts, and add chicken or beans to the pasta.
Building a meal that lasts
Aim for roughly twenty to thirty grams of protein at each meal, which looks like three eggs, a cup of Greek yogurt, a palm-sized piece of chicken or fish, or a cup of lentils with rice. Fill half the plate with vegetables or fruit, and choose the whole-grain version of the starch when it is on offer, since the fiber is what buys you the extra hours. Breakfasts that work include eggs on whole-grain toast, plain yogurt with fruit and nuts, and oatmeal made with milk and topped with nut butter. Try not to go more than four or five waking hours without eating.
Water and caffeine
Mild dehydration feels exactly like tiredness, with a dull headache and poor concentration. You do not need to count glasses. Pale yellow urine means you are drinking enough, and dark yellow means you are behind. Up to about 400 milligrams of caffeine a day, around four small cups of brewed coffee, is considered safe for most healthy adults. Caffeine blocks the feeling of fatigue rather than supplying energy, so the bill comes due later. Stop by early afternoon to protect your sleep, and read the label on energy drinks, which can carry several cups' worth of caffeine plus a great deal of sugar in one can.
When food is not the cause
Tiredness that persists for weeks despite decent meals and enough sleep deserves a blood test, not another coffee. Iron deficiency is common, particularly in people who menstruate and in those who eat little meat. Low vitamin B12 is a known risk of a vegan diet without supplements. Thyroid problems and sleep apnea also present as plain exhaustion. Ask your doctor before starting iron on your own, because too much of it is harmful.
Tip Keep one emergency snack with protein in your bag or desk, such as nuts or a plain jerky. It costs a dollar and prevents the four o'clock vending machine decision.
