Eating healthy fats for conception
Apr 15 • 2016

A healthy weight for conception and pregnancy

To find out if you are overweight or underweight, the first step is to assess whether your weight falls within the ideal range for conception. The body mass index calculation is useful as a general guide. The ideal range for conception, the fertility zone, is a slightly narrower range than for the general population (BMI between 20-24, with the ideal being around 21). You can calculate your BMI by using this equation: divide your weight in kilograms (kg) by your height in metres (m), then divide the answer by your height again to get your BMI. There is an online NHS tool you can use: ( If your BMI indicates that you are under or overweight, taking small steps to gain or lose a little weight can often be enough to improve ovulation.

But what to eat to maintain a healthy weight or to gain or lose a little? The current controversial debate on low-fat versus low-carb has been further fuelled by the recent publication of a report by the National Obesity Forum and the Public Health Collaboration which claimed that public health dietary guidelines urging low-fat diets are having “disastrous health consequences”. This has left many confused – particularly those who have tried to adhere to a low-fat diet for years – about how much and what types of fat to eat. For more people, sugar is replacing fat as public enemy number one. But a headline saying “Eat fat and get thin” does not help to clear up the confusion nor clarify the message.

First, it is important to remember that fat is an essential nutrient and one of the primary energy sources for the body. We need fat in our diet to support immune function, healthy hormonal balance and to control inflammation in the body. Some of the essential micronutrients required for conception are fat-soluble which means for our bodies to absorb these nutrients we need to eat them with fat.

Good fat sources in the diet are important for women who are underweight and overweight. When women adopt low-fat diets, oestrogen levels drop noticeably in a very short time and this can disrupt their menstrual cycle. But if we need fat, will any type of fat do? It won’t surprise you to know that not all fats are equal. So avoid fatty processed foods and processed fattier meats and choose oily fish, eggs, whole dairy products, nuts and seeds, avocado and olive oil which are highly nourishing and wholesome sources of fat in the diet. These high-fat foods are the basis of the Mediterranean diet and a 2010 Dutch study showed that having a Mediterranean style diet increased chances of conception by 40%.

Avoid low-fat products that may be high in sugar or sugar alternatives and ensure dairy sources are not low-fat. The Harvard University Nurses’ Health Study found that the more low-fat diary products in a woman’s diet, the more trouble she had getting pregnant. And when we eat fat, we feel fuller for longer and eat less overall.

So fat is necessary but try to choose wholesome sources of fat in your diet and aim to keep your BMI in the fertility zone between 20 and 24.

I will address carbohydrates and other aspects of healthy eating in another post but the take home message is not to cut out the fat when managing your weight but to ensure you choose healthy fats that promote fertility and well-being.

Victoria Wells is the Nutritionist at Emma Cannon’s Fertility Rooms
Individualised programmes are devised for weight management, female and male fertility, IVF preparation and the Body Mind Gut to improve gut health.