World Green Organisation Announces New White List for Pregnancy Supplements (Seventh Instalment of the White List launch)

An increasing number of people now choose to take health supplements as a way to improve their health and make up for any deficiency as a result of irregular diet. This is especially true for expectant mothers. In order for them to give their children a healthy head start in life, many pregnant women will look for additional health products that supplement pregnant women and foetus’s nutrition. However, World Green Organisation (WGO) believes that since the specific health needs for pregnant and non-pregnant women are different, there needs to be an increased knowledge of these supplements and how excessive ingestion can gravely affect foetal development and maternal health. Research found that excessive usage and ingestion can cause foetal malformation or autism in the baby. People who are interested in purchasing pregnancy supplements should refer to the ‘White List’ to facilitate purchase decision. Please also consult your doctor before taking supplements.

There are many different types of health supplements that are available. Some are liquids, granules, or capsules. The many choices and types that advertise its convenience and fast results make it confusing for customers to choose. In order to set a higher safety standard and protect the public’s health, WGO partnered with three internationally recognised laboratories and developed a three defence methodology to test products that are in the market[1]. Products that pass the three defence methodology will be put on the ‘White list’. Today WGO announced the new ‘White List’ for pregnancy supplements, the seventh instalment of the ‘White List’ launch.

Common Pregnancy Supplements and their uses
The most common pregnancy supplements include vitamin A, vitamin D, folic acid, calcium, iodine and iron. Vitamin A, vitamin D, and calcium help increase immune function, and promote bone and foetal teeth growth. Vitamin A helps to improve eyes and skin of the pregnant mother and foetus. It is said to help prevent night blindness. Folic acid helps to reduce the risk of neural tube defects and congenital abnormalities. Some studies have found taking folic acid can reduce the chance of autism in the foetus. Calcium decreases probability of pregnancy-induced hypertension. Iodine and iron are important for oxygen transport and healthy growth and development of foetus and placenta. Iodine supports the thyroid function and improves human metabolism in pregnant women and foetuses. Iron supplements diminishes the likelihood of iron deficiency anaemia and postpartum anaemia.

Excessive ingestion risks
Although there are a lot of benefits to taking these supplements during pregnancy, people need to be careful to not over eat them. If the body takes in too many of these supplements, the first part of the body to be affected is the liver. The liver helps to detoxify substances in the body. Since vitamin A and D are fat soluble vitamins, they get stored and metabolised in the liver after absorption which makes any risk and problems from over eating the supplements even greater.

Excessive fat soluble vitamins can negatively affect foetal development
Too much of a good thing can be bad for the body. An excessive accumulation of vitamins such as vitamin A can cause acute poisoning, nausea, vomiting and blurred vision. Excessive amounts of vitamin D causes vitamin D toxicity. Vitamin D toxicity is the build-up of calcium in the blood which can cause nausea, vomiting, and kidney problems such as the formation of calcium stones. It can also cause hypertension, bone and joint pain due to calcification of soft tissues for pregnant women. In severe cases, it can affect the foetus of the pregnant women and can cause foetal growth retardation. The foetus may also be more likely to be allergic to peanuts, soy and other foods after birth.

Excessive water soluble vitamins can cause premature death
Many people think that there is nothing to worry about ingesting excessive amounts of water soluble vitamins such as vitamin C and folic acid, since they leave the body through sweat or urine. However, excessive intake of vitamin C can cause the body to become too acidic and affect the absorption of folic acid. Taking too much folic acid can cause irreversible neurological damages especially for pregnant women.

Too little and too much intake of folic acid can increase the risk of autism
In addition to taking account the amount of folic acid ingested, research found that people also need to take notice of when to take folic acid. The Norway Mother and Child Cohort, supported by the Norwegian Ministry of Health and Care Services, conducted an analysis of more than 85,000 mothers and their newborn babies on the use of folic acid from 4 weeks before to 8 weeks after the start of pregnancy. They published their findings in 2013 which found that pregnant women who took folic acid in moderate amounts (3-5 times/week) during pregnancy was associated with decreased risk of ASD (Autism Spectrum Disorder). Low (less than 2 times/week) and high (more than 5 times/week) were associated with increased risk of ASD. Another study from 2013 found that women who take folic acid supplements 4 weeks before to 8 weeks afterwards reduced the child’s risk of autism by 40%. [2]

Another study published in the Paediatric and Perinatal Epidemiology last year followed over 1,250 mother-child pairs at the Boston Medical Centre to determine the relationship between maternal multivitamin intake and ASD risk in offspring. They found that there was a ‘U shaped’ relationship between supplementation frequency and ASD risk. This means that if folic acid is taken too early or too late, too little or too much, it can increase the ASD risk in infants. [3]

Overdoes of minerals can also have long term consequences
An overdose of various minerals can also have severe consequences. Calcium interferes with gastrointestinal functions. Pregnancy hormones cause intestinal muscles to relax and delay the processing of food in the body. Taking too much calcium can worsen constipation as calcium carbonate reduces the frequency of bowel movement. In severe cases, excess amounts of calcium in the body can cause kidney stones. Too much supplementation of iodine, especially during pregnancy can increase the risk of developing iodine-induced thyroid dysfunction and may even cause miscarriage or premature birth. In extreme cases, the foetus may suffer from congenital hypothyroidism. Ingesting excess iron creates similar issues and situation to excess iodine. It can cause premature birth, low birth weight, or even miscarriage.

Hidden costs of Omega 3 fish oils
Another frequent health supplements are Omega 3’s which are often found in the form of DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid). Fish oil tends to extract the fatty acid EPA from deep sea fishes such as menhaden herring, salmon, and sharks. However, due to the anticoagulant effect of EPA, excessive amounts may cause bleeding problems for pregnant women. Therefore, it is recommended that pregnant women should decrease usage and ingestion of EPA-containing fish oils or related health food in the late trimester of the pregnancy.

Differences between natural and artificial health foods
Dr. Ivo Chen Siu Wai, an obstetrics and gynecology specialist noted that although it is a general consensus that the nutritional value of natural and synthetic vitamins are similar, there are studies which indicate that the body’s ability to absorb vitamins such as vitamin E are different. Natural health supplements are derived from food sources and are said to have a better absorbent rate than synthetic vitamins. Studies have found that synthetic vitamin E gets expelled by the body 3 times faster than natural vitamin E. Dr. Chen also added that vitamins also work together sometimes for a similar effect. Vitamin D3, magnesium, and vitamin B12 can help absorb calcium and folic acid respectively. Vitamin C can improve the body’s ability to absorb iron.

It is advisable to consult your doctor before consumption
Dr Chen continued

The needs of pregnant women are different from those that are not pregnant. Some health supplements that can be taken regularly may not be suitable for use during pregnancy. In addition, vitamins are naturally found inside the food we eat. For example, milk is rich in vitamins A, D, folic acid, and calcium. Eggs and kelp have iodine and iron. Since a lot of food that we eat already have naturally occurring vitamins, eating additional health supplements may cause the consumer to have excessive amounts. It is important to first consult a doctor or a professional before adding health supplements to your diet, especially for pregnant women.

She also reminded the public that everybody’s stomach is different. The way the body processes and react to granules, pills, capsules, or gels differ person to person. Therefore, if you feel unwell after eating, you should stop or switch the form of health supplements.

Health supplements raise environmental concerns
Some health supplements may be linked to environmental concerns. A popular health supplement is DHA from fish oil. The Taiwan Environmental Information Association announced that the production of fish oil is a contributor to overfishing. A fish oil company was found guilty of overfishing menhaden herring and was banned from fishing in 13 west coast states of the United States. The manufacturers of the fish oil company argued that there was no overfishing and that the fish was not extinct. A decrease of species disrupts the food chain and ecosystem. Algae is the fish’s main source of food. Because there is less fish eating the algae, the algae has over-proliferated. This is not good for multiple reasons. When there is a lot of algae, the water becomes cloudy and blocks light to underwater grass that provides food and shelter for many marine animals. In addition, algae bloom takes up oxygen in the ocean exhaustively which changes the marine environment and make it unhealthy for fishes, plants and other marine animals. Currently there is an excessive fishing of wild salmon and sharks which has made caused an imbalance in the food chain and marine ecosystem.

Furthermore, the water has been found to be contaminated by heavy metals in recent years. Since fish oils come from fishes that live in these waters, the fish oils may also contain heavy metals which can negatively affect human health.

Dr William Yu, Chief Executive Officer of World Green Organisation suggested that,

In order to avoid overfishing and be more environmentally friendly, we can replace DHA fish oils with manmade algal oils for omega-3. Menhaden herrings have a rich DHA content because of their algae diet. This means that algal oils will provide the same amount of health benefits as fish oils. Replacing fish oils with algal oils will be more environmentally friendly, help to avoid overfishing, and lower the risk of EPA and heavy metals.

Avoid health supplements that have expired
WGO would also like to remind the public to avoid eating expired health supplements as efficiency of the health supplements decrease when they are expired. Water-soluble vitamins are more susceptible to deliquescence which is when high humidity causes water-soluble solids to dissolve. This makes the vitamin no longer as nutritious. Fish oils are prone to oxidizing and acidizing which gives off odours and produces lipid peroxides that increases the risk of cardiovascular diseases.

Products that have passed the three defence methodology is put onto the ‘White List’. For this product category, all products were also tested to ensure that levels of calcium, iron, iodine, and EPA were within the acceptable limit. (For more details on the methodology, please refer to Appendix 2. Please see Appendix 3 for details on the additional tests for this product category.)

This project began at the end of 2016. Since its inception, WGO has announced 6 launches of ‘White List’ including baby lotion (I&II), baby cream, balm/ointment (I&II), baby oil, and baby wash. WGO will continue to test different product categories in the future. Through this project, WGO aims to educate consumers on product safety standards and incentivise manufacturers, suppliers, and retailers to pursue higher safety standards.

About Us

The World Green Organisation (WGO) is an independent non-governmental organisation concerned with environmental conservation and environmentally related livelihood and economic affairs. Through science-based policy research and community projects, the WGO aims to enhance the quality of the environment, promote a greener economy, and improve people’s livelihoods. In particular, it will focus on the social concerns of underprivileged groups and on the creation of a green economy to help realise its vision of sustainable development. For more information, please visit


For inquiries:

CEO Dr. William Yu
Tel: 2391 1693
Manager, Communications Ms. Noel Wong
Tel: 2991 9119

[1] The samples of prenatal supplements include online purchasable ones from the Mainland market

[2] Association Between Maternal Use of Folic Acid Supplements and Risk of Autism Spectrum Disorders in Children, JAMA Network, JAMA: Journal of The American Medical Association, 309, 6, pp. 570-577, February 13, 2013

[3] Maternal Multivitamin Intake, Plasma Folate and Vitamin B12 Levels and Autism Spectrum Disorder Risk in Offspring, Paediatric and Perinatal Epidemiology, 2018, 32, 100–111