Women have special bike fits, shoe designs and race categories, so it only makes sense that female athletes have different nutrition needs than their male peers. While it seems obvious, this topic is not clear cut. Most research on athletic training, nutrition and medication are done on male subjects, leaving women's needs up for interpretation and less studied.
Thankfully, when it comes to performance nutrition, most guidelines and suggestions are based on body weight, composition and training metrics (duration/time/intensity) that work for both genders. Even with the attempt to create equal advice for all, there are some areas of sport nutrition that are unique to a women's needs.
Daily Calorie Needs
Daily calorie needs are based on body size; smaller bodies need less than larger bodies/muscle mass. Muscle requires more energy than fat and activity level, and the more you move, the more you burn! Women with smaller bodies and less muscles than men will burn and require fewer calories.
Don't Obsess Over Calorie Intake
Female athletes involved in weight related sports—for performance or aesthetic reasons—are more at risk of disordered eating, which can lead to poor mental health and malnourished bodies. Don't obsess over calorie intake. Instead, focus on the quality of calories and being in touch with hunger cues.
Women Burn More Calories From Fat
During exercise of any intensity and duration, women burn more calories from fat compared with men.
Women typically store more subcutaneous (beneath the surface) fat and less visceral (around the organs) fat, so while you might not love the way it looks, it is generally a healthier fat to have.
Work Harder to Build Muscle
Testosterone promotes muscle tone and estrogen promotes fat storage. Females might need to work extra hard to build muscle because of this and should not shy away from spending time in the weight room or consuming high-quality proteins.
Slow Caffeine Metabolizers
Females are more likely to be slow caffeine metabolizers, meaning the substance takes longer to kick in and stays in your system longer. This means you'll want more time between consuming and performing to see the benefits, and you'll need to stop consuming it earlier in the day to avoid putting your sleep at risk.
Research shows carbohydrate loading is only effective when women consume 10 to 12 grams per kilogram of body weight for 48 hours prior to the event. Most women under-consume carbohydrates, rendering this performance strategy useless.
Iron Is Even More Important
Iron is a critical nutrient for carrying oxygen-rich blood cells to working muscles. Due to menstrual blood loss, the finicky nature of this mineral—and the fact that many female athletes consume less meat—means there is a serious risk of becoming iron deficient.
Ease Into Changes
Women's hormones are also very sensitive day to day and are susceptible to changes in stress, training and nutrition intake. When starting any new routine (like intermittent fasting or a new training plan) it is advised that women take it very slow and ease into the changes to not heavily disrupt hormone levels and signals.
More Gastric Distress
Active females tend to have more gastric distress during exercise. This might be due to consuming high amounts of roughage and fiber or being more sensitive to nerves and anxiety.
Take Your Cycle Into Account
Nutrient needs are very dependent on monthly cycle phase and phase of life (pregnant, breast feeding, menopausal, etc.). It is very important to reevaluate your diet, fitness and goals when you enter a new phase.
Fast for Shorter Durations
While women can benefit from intermittent fasting just as well as men, female hormones are too sensitive to starvation to handle extended fasts. If this is something you'd like to experiment with, aim for short duration fasts of 12 to 16 hours, and ease your way into it.
Avoid Restrictive Diets
Eating restrictive diets puts women at risk for under-consuming crucial nutrients that fit females need to be concerned with, such as folate, calcium, iron, zinc, Vitamin D and B12.
Under consuming calories and carbohydrates puts reproductive health at risk. Excessive fatigue, low bone density and the absence of menstrual cycle are risk factors.
Energy availability is the best method of assessing adequate energy and health demands for female athletes. They should aim to take in 45 calories per kilogram of fat free mass each day. Consuming less than 30 calories per kilogram per day is shown to risk bone quality, mental well-being, performance and reproductive health.
Females at any level of activity need and will benefit from paying extra attention to their nutrition. All women should routinely get checked for hormone and nutrient levels to ensure on-going health, as it is difficult to see if anything is wrong until your health is negatively affected. Working one on one with a sports dietitian can help you make sure your diet is the best it can be to promote health and performance.
READ THIS NEXT: The Pros and Cons of Tracking Your Food