Food safety Archives | Lifestyle Maternity

Diet and Fertility, Fertility, Food safety, Fruit & Vegetables, Preconception, Pregnancy

Understanding the MTHFR gene in pregnancy

The MTHFR gene plays a crucial role in human health, particularly during pregnancy.

It provides instructions for creating an enzyme called methylenetetrahydrofolate reductase. This enzyme is essential for processing folate, a B vitamin crucial for cell growth and development.

Part of this development is of the baby’s ‘neural tube’. Normally, during the first month of pregnancy, the two sides of the fetus’s spine (backbone) join to cover and protect the spinal cord, spinal nerves and meninges (the tissues covering the spinal cord). At this point, the developing brain and spine are called the neural tube.

Understanding MTHFR Gene Variations

The MTHFR gene is highly variable, with several common variations in the instructions for how the gene ‘works’ or is ‘read’. These variations are also called polymorphisms.

Two of the most well-studied MTHFR polymorphisms are:

C677T: This variation occurs at position 677 of the gene, where a cytosine (C) nucleotide is replaced by a thymine (T).
A1298C: This variation occurs at position 1298, where an adenine (A) is replaced by a cytosine (C).

It’s important to realise that a polymorphism is a variant within a gene that does NOT necessarily affect its function, unlike a pathogenic mutation.

We regularly get asked about the MTHFR enzyme…

It’s easy to get freaked out when you go down a ‘Dr Google’ rabbit hole. There is a lot of (mis)information about this enzyme online.

Fortunately, two experienced Australian clinicians have recently outlined important facts about the controversies and clinical implications of this enzyme. (1)

What do the experts say?

Long and Goldblatt point out that there are two predominant MTHFR polymorphisms, 677C>T and 1298A>C. They note that, in the general population, 60–70% of people will have at least one of these variants (be heterozygous), 8.5% will be homozygous for 677C>T or 1298A>C, and 2.25% will be compound heterozygous. Overall, 10% of the population will be homozygous or compound heterozygous for these two polymorphisms.

The MTHFR polymorphisms in the homozygous or compound heterozygous form only reduce enzyme production mildly and are thus of LIMITED pathogenicity. The 677C>T polymorphism in the homozygous form may result in MILD homocystinuria due to decreased MTHFR activity. The 1298A>C polymorphism does not cause homocystinuria in a heterozygous or homozygous form, but may affect enzyme activity when inherited with the 677C>T polymorphism.

Given the prevalence of the MTHFR polymorphisms (60–70% of the population) and the frequency of neural tube defects (approximately 1 in 1000 in Australia), it is UNLIKELY that the polymorphisms alone have a significant role in the formation of neural tube defects.

While there may be some increased risk of neural tube defects in individuals with the homozygous 677C>T variant, the level of risk has not been quantified and the impact of environmental factors, such as folate supplementation, has a more significant role.

So, WHAT does this all mean?

These authors suggest that, on the basis of the available scientific evidence, there are very limited clinical indications for testing for the 677C>T and the 1298A>C polymorphisms in the MTHFR gene. They say that testing is not indicated as a non-specific screening test in the asymptomatic general population.

The attention paid to this enzyme is out of proportion to the known association of folate deficiency and neural tube defects in pregnancy.

The take away message is that it’s more important to find and help women with low folate intake before pregnancy than to worry about something that impacts very few women.

Did you know that population-level fortification of folate results in a decrease in the incidence of neural tube defects by about 70%.(2)

This has been demonstrated through a significant drop in neural tube defects when population-level fortification of folate occurred.

Knowing the importance of folic acid before and in early pregnancy AND due to low intake of folate before and during pregnancy the Australian and New Zealand Governments introduced food fortification.

From September – October 2009, Food Standards Australia New Zealand (FSANZ) developed a mandatory folic acid fortification standard to help reduce the incidence of neural tube defects. They also brought in a mandatory iodine fortification standard to address the re-emergence of iodine deficiency in the population.

This involves the addition of folic acid to bread-making flour in Australia (all except organic and gluten free flours) and iodine (via iodised salt) to bread in Australia and New Zealand.

So, is the amount of folate in food enough for me before and during pregnancy?

No, it’s still essential to take a supplement.

FOLIC ACID. This is the most important supplement to take when trying to conceive, as it helps prevent neural tube defects in the developing baby. Most women need to take a supplement that contains at least 400 micrograms (mcg; µg) of folic acid per day, starting at least one month before conception and during the first trimester (at least). Some women need higher amounts – these include women with diabetes, a higher body mass index, those with a family history of neural tube defects, or who are taking certain medications.

Additionally, while iodine is not directly related to improving fertility it is essential to take during all of pregnancy and while breastfeeding. Iodine is involved in growth and development, especially for a baby’s brain. Studies show that the Australian population is mildly iodine deficient. Pregnant women need 220 micrograms of iodine per day. All women should take a daily supplement with 150 micrograms during pregnancy and breastfeeding.

What are good food sources of folate and iodine?

Well planned nutrition, especially folate intake, is crucial for all pregnant women, regardless of MTHFR gene status.

Folate-rich foods:

Leafy green vegetables,
citrus fruits,
beans and legumes, and
fortified breads and cereals.

Iodine rich foods:

Most breads and cereals (these are now made with iodised salt)
Vegetables (depending on the quality of the soils they are grown in)
Fish and seaweed (but remember food safety tips in pregnancy), and
Iodised salt (use over other salts, but for heart health – use sparingly)

Key takeaway: The MTHFR gene plays a role in folate metabolism, and variations in this gene may have implications for pregnancy outcomes. While research in this area is ongoing, maintaining a healthy diet rich in folate AND supplementing with a supplement containing 400mcg of folic acid in at least the month before and the first trimester of pregnancy is essential.

To find out more about pregnancy supplementation read here.

We also have a blog about fertility supplementation here.

REFERENCES:

Long S & Goldblatt J. (2016). MTHFR genetic testing: Controversy and clinical implications. Australian Family Physician. 45(4) https://www.racgp.org.au/afp/2016/april/mthfr-genetic-testing-controversy-and-clinical-imp
Bower C, Stanley FJ. Dietary folate as a risk factor for neural tube defects: evidence from a case-control study in Western Australia. Med J Aust 1989;150:613-9.

Image: deoxyribonucleic acid

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1 February 2025/by Dr Shelley Wilkinson

Dietary Quality, Food safety, Fruit & Vegetables, Gestational Diabetes, Morning Sickness, Pregnancy, Recipes and Meal Ideas, Weight

PODCAST – Eating for Two? Peak Nutrition for Pregnancy

Recently, our Director and Principal Dietitian, Dr Shelley Wilkinson spoke with Laureate Professor Clare Collins about pregnancy nutrition.

In this podcast Clare and Shelley cover nutritional needs of pregnancy. Topics they discuss include the importance of a nourishing, high quality diet in pregnancy, food safety, weight gain, and recommended supplements. They back up these facts with the nutrition science that sits behind the recommendations and practical solutions to achieve these goals.

Listen here or through your favourite streaming service.

Dr Shelley’s featured recipe on No Money, No Time.

1 September 2024/by Dr Shelley Wilkinson

Dietary Quality, Food safety, Pregnancy

Busted! (PART 2). Three more myths about pregnancy nutrition: Supplements, morning sickness, and food freedom

Congratulations! You’re embarking on an incredible journey of pregnancy. Amidst the excitement, there’s also a whirlwind of information (and sometimes misinformation) about what to do (and not do) to ensure a healthy pregnancy.

Nutrition plays a crucial role, and navigating myths surrounding supplements, morning sickness, and food choices can feel overwhelming.

Last month we looked at the myths of ‘eating for two’, pregnancy food cravings and weight gain in pregnancy. This month let’s debunk three more myths so you can feel empowered to make informed choices about nourishing yourself and your growing baby.

Myth #1: Pregnancy Vitamins Guarantee All Your Nutritional Needs

Despite a strong marketing push, pregnancy multivitamins (or the “pink” multivitamins) are not required by most women.

There are only two essential nutrients recommended for pregnancy:

folic acid, crucial for reducing the chance of neural tube defects in your baby, and
iodine, for growth and development, especially of baby’s brain.

Other nutrient supplements that may be required if a deficiency is diagnosed (iron, vitamin D, vitamin B12), someone is at risk of pre-eclampsia (calcium) or women avoid certain food groups, such as vegetarians or vegans (iron, vitamin B12).

Remember: A well planned and balanced diet is the foundation of a healthy pregnancy. A food first approach is best for most nutrients needed.

Dietary supplements play a specific and supporting role, rather than acting as an insurance policy “just in case”.

Myth #2: Morning Sickness Means You Can’t Eat (or You Have to Eat Bland Foods Only)

Morning sickness, though often referred to as such, can strike any time of day. Feeling nauseated can make the thought of food unappealing, but avoiding food can actually worsen the symptoms.

Taming the Tummy Troubles:

Small and Frequent Meals: Opt for smaller, more frequent meals throughout the day to avoid an empty stomach.
Find Your Triggers: Identify foods that worsen your nausea and avoid them temporarily.
Hydration is Key: Stay hydrated by sipping water or clear fluids throughout the day. Ginger tea may also help soothe nausea.
Bland Doesn’t Have to Be Boring: Bland foods like crackers or toast can be your lifesaver, initially. But explore other easily digestible options like crunchy dried breakfast cereals, yoghurt, fruit smoothies, or mashed potatoes.

Don’t Fear Flavour:

While some bland foods might be comforting initially, don’t feel limited. Experiment with different flavours and textures that appeal to you. Ginger, peppermint, and citrus can sometimes help settle your stomach.

Myth #3: There’s a Long List of “Forbidden Foods” During Pregnancy

Sometimes it can feel like the list of foods to avoid in pregnancy is longer that what you are allowed to eat. Due to changes in a woman’s immune system during pregnancy, you are more susceptible to food poisoning.

This is from the usual culprits – Salmonella, E.coli and Campylobacter – but also one you hear a lot about in pregnancy, Listeria.

However, if you avoid all foods that carry a risk for harbouring listeria, it is likely that you will consume fewer nutrients. This is not ideal as you ARE growing a baby.

You don’t have to go without! For every item on the “no” list, there are a number of alternative and this table will help to make those choices (source).

Foods to avoid

Safe alternatives to enjoy

· Deli meats

· Pre-sliced and pre-packaged meats

· Cold ready to eat chicken

· Meats cooked at home

· Tinned fish (two to three times per week)

· BBQ chickens, if eaten immediately when hot

· Chilled or raw seafood

· Sashimi or sushi

· Smoked salmon (or other smoked fish varieties)

· Oysters

· Pre-cooked shellfish including prawns and crabs

· Tinned fish including salmon and tuna (two to three times per week)

· Freshly cooked seafood, including shellfish, eaten hot

· Pre-packaged or pre-cut fruit, vegetables and salads

· Salad and sandwich bars

· Buffets

· Homemade salads with freshly washed ingredients

· Freshly cut and washed fruit

· Canned or frozen fruit and vegetables

· Soft cheese including brie, camembert, ricotta, feta and blue cheese

· Pate or meat spreads

· Hard cheeses such as cheddar

· Processed cheese

· Cream cheese spreads

· Plain cottage cheese

· Soft cheeses that are cooked and eaten when hot

Freedom with Responsibility:

Beyond these exceptions, you can enjoy a variety of foods during pregnancy.

Here’s what to prioritise for a healthy pregnancy diet:

Fruits and Vegetables: Aim for a rainbow! They provide essential vitamins, minerals, and fibre.
Whole Grains: Choose wholegrain bread, low GI brown rice, quinoa, and oats for sustained energy and healthy digestion.
Lean Proteins: Include protein sources like chicken, fish (excluding mercury-rich varieties), beans, lentils, and tofu for building and repairing tissues and supporting your baby’s growth.
Healthy Fats: Don’t fear healthy fats found in avocados, nuts, seeds, and olive oil. These are essential for fetal brain and eye development.

NEED MORE HELP?

We offer individual consultations and self-paced online courses as we know you all have different learning styles and budgets. Attending an individual session OR online course with a Lifestyle Maternity dietitian will allow you to assess your diet against recommended guidelines and identify changes that can be tailored to your lifestyle and dietary preferences.

In our self-paced online course you will be encouraged and guided to assess your own health habits against pregnancy recommendations, participate in activities around setting health goals for optimal nutrition and learn how to adapt your routines with confidence to achieve these goals to make them stick. More information here.

An individual consult involves a more thorough assessment of your dietary and lifestyle patterns with a personalised action plan being developed in collaboration with the dietitian. If you would like further information book an appointment now.

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1 August 2024/by Dr Shelley Wilkinson

Food safety, Pregnancy, Recipes and Meal Ideas

Why am I told to avoid so many foods in pregnancy? Understanding food safety in pregnancy.

Sometimes it can feel like the list of foods to avoid in pregnancy is longer that what you are allowed to eat. Due to changes in a woman’s immune system during pregnancy, you are more susceptible to food poisoning. This is from the usual culprits – Salmonella, E.coli and Campylobacter – but also one you hear a lot about in pregnancy, Listeria.

What is Listeria?

During pregnancy women are more susceptible to getting Listeriosis by eating foods containing the bacteria Listeria which can cross the placenta. Symptoms may include fever, headache, tiredness, aches, pains, diarrhoea and/or nausea. It’s important to note that while symptoms may be mild in pregnant women, it can result in miscarriage, premature birth or, in rare cases, stillbirth.

What does this mean for me now that I’m pregnant?

This means extra care is needed for food storage, preparation and, of course, selection. To help reduce the risk of getting Listeriosis, here are the key things to remember:

Practice good food hygiene by washing fresh fruit and vegetables before you eat them
Refrigerate leftovers and consume within 24hours, reheating to a visibly steaming temperature
Avoid buffet meals or ready-to-eat sandwich and salad bars
Avoid raw or cold seafood
Consume only dairy products that have been pasteurised
Avoid soft serve ice-cream or milkshakes/thick shakes with soft-serve as an ingredient
Ask for all meats to be well-cooked
Deli meats, including pre-packaged or freshly sliced off the bone, soft cheeses and pate should be avoided
Ensure eggs are cooked through, no runny yolks!
All sushi varieties should be avoided
Actively discuss menu options with restaurants and cafes to make sure your meals are freshly prepared