by Sue Bedford (MSc Nutritional Therapy)
We speak a lot about foods and key nutrients that help to support fertility, but what about those that should be avoided or moderated where possible?
When it comes to fertility- one to avoid are Trans-fats.
Trans-fats are liquid oils that have been turned into solids by a process called hydrogenation and are in thousands of pre-prepared foods to give texture and a long shelf life.
Examples of SOME foods that may contain Trans-fats (check the label for hydrogenated fats):
French fries/some chips
Most things that are battered or fried
Some ice creams
Frozen microwave meals
Impact on fertility
Consumption of Trans-fats can lead to obesity which may impact on fertility by affecting ovulation, increasing insulin resistance and also increasing inflammation. Trans-fats seem to amplify the symptoms of PCOS and endometriosis in some women.
Researchers from Harvard Medical School investigated 18,800 women and looked at the effect of Trans-fats on fertility. They discovered that a consumption of 2% Trans-fats in the diet doubled the risk of infertility (Chavarro et al 2007). This could be explained by the fact that eating more of these fats usually means eating less of another type of fat or carbohydrate.
Trans fats increase inflammation throughout the body, interfering with ovulation, conception and early embryonic development and this may affect IVF success. Eating monounsaturated fats instead of carbohydrates or trans fats may support fertility, ease inflammation and improve the body’s sensitivity to insulin. The United States Department of Agriculture’s Dietary Guidelines for Americans recommend that trans fat intake should be as low as possible (U.S Department of Agriculture 2005). Some experts believe they should be avoided completely as they may impair fertility by affecting ovulation.
What can you do?
Start reading labels. Avoid foods that contain trans fats in the ingredients.
Eat whole foods in their natural state. Focus on fresh vegetables, fruits, organic meats and fish. Introduce more smoothies and juices into your diet and ensure that they contain more vegetables where possible.
Avoid fast foods- chips (French fries – make your own!) bought burgers (buy from your local butcher or make your own) fried chicken… are all cooked in trans fats.
Another one to avoid where possible is refined sugar
Sugar itself is not a food group although it is naturally present in certain foods such as fruits. Excess sugar consumption can lead to inflammation, hormone disruption – which may affect fertility, continued stimulation of the adrenal glands, yeast infections, lowered immunity, (may contribute to) leptin resistance, along with increasing LDL(bad) cholesterol and triglycerides in the body.
Excessive consumption of refined carbohydrates erratically throughout the day will cause blood sugar levels to rise and fall, leading insulin levels to peak and trough, which eventually may lead to insulin resistance. Insulin excess may affect ovulation and lead to increased inflammation in the body This can impact on key fertility hormones such as Testosterone which impacts sufferers of Polycystic Ovarian Syndrome (PCOS).
What can you do?
Try to eat 3 distinct meals per day, and if you need to have a snack try a handful of nuts/seeds, some sugar snap peas or baby corn and dip into homemade guacamole.
Consume the following foods to help control blood sugar levels:
Nuts and seeds
Foods with a low Glycemic load
Complex carbohydrates – oats, wholemeal bread, sweet potato
Oily fish – wild salmon, sardines, mackerel
Chromium rich foods – onions, turkey, potatoes, broccoli.
Most vegetables especially root vegetables/leafy green vegetables
Legumes e.g beans, peas, lentils, kidney beans
For more information about fertility foods, head to our nutrition page where you will find an abundance of information and recepies.