Unhealthy diet during pregnancy could be linked to ADHD

New research led by scientists from King's College London and the University of Bristol has found that a high-fat, high-sugar diet during pregnancy may be linked to symptoms of ADHD in children who show conduct problems early in life.

Published in the Journal of Child Psychology and Psychiatry, this study is the first to indicate that epigenetic changes evident at birth may explain the link between unhealthy diet, conduct problems and ADHD.

Early onset conduct problems (e.g. lying, fighting) and attention-deficit/hyperactivity disorder (ADHD) are the leading causes of child mental health referral in the UK. These two disorders tend to occur in tandem (more than 40 per cent of children with a diagnosis of conduct disorder also have a diagnosis of ADHD) and can also be traced back to very similar prenatal experiences such as maternal distress or poor nutrition.

In this new study of participants from the Bristol-based 'Children of the 90s' cohort, 83 children with early-onset conduct problems were compared with 81 children who had low levels of conduct problems. The researchers assessed how the mothers' nutrition affected epigenetic changes (or DNA methylation) of IGF2, a gene involved in fetal development and the brain development of areas implicated in ADHD - the cerebellum and hippocampus. Notably, DNA methylation of IGF2 had previously been found in children of mothers who were exposed to famine in the Netherlands during World War II.

The researchers from King's and Bristol found that poor prenatal nutrition, comprising high fat and sugar diets of processed food and confectionary, was associated with higher IGF2 methylation in children with early onset conduct problems and those with low conduct problems.

Higher IGF2 methylation was also associated with higher ADHD symptoms between the ages of 7 and 13, but only for children who showed an early onset of conduct problems.

Dr Edward Barker from King's College London said: 'Our finding that poor prenatal nutrition was associated with higher IGF2 methylation highlights the critical importance of a healthy diet during pregnancy.

'These results suggest that promoting a healthy prenatal diet may ultimately lower ADHD symptoms and conduct problems in children. This is encouraging given that nutritional and epigenetic risk factors can be altered.'

Dr Barker added: 'We now need to examine more specific types of nutrition. For example, the types of fats such as omega 3 fatty acids, from fish, walnuts and chicken are extremely important for neural development.

'We already know that nutritional supplements for children can lead to lower ADHD and conduct problems, so it will be important for future research to examine the role of epigenetic changes in this process.'

Exercise during pregnancy protects the next generation from age-related health risks

Exercise during pregnancy may be as effective in protecting the next generation from age-related health risks as efforts made during the offspring's own adulthood, new research suggests. Kevin Pearson, associate professor at the University of Kentucky Department of Pharmacology and Nutritional Sciences, will present preliminary findings on the long-term effects of physical activity during pregnancy at the American Physiological Society's Integrative Biology of Exercise 7 meeting in Phoenix.

Oxidative stress is damage to the body caused by an accumulation of unstable molecules called free radicals. The buildup of free radicals decreases resistance to stress and increases the risk of obesity and age-related and chronic disease. Reducing oxidative stress can help lessen the risks of conditions such as cancer, heart disease and type 2 diabetes.

The research team examined markers of oxidative stress, inflammation and insulin sensitivity in mice that were born to mothers who were exercised while pregnant. The offspring of the exercised mice had better stress resistance and improved insulin sensitivity, even into adulthood, than those born to sedentary mothers.

"To date, caloric restriction has been the most reproducible and promising intervention to improve these outcomes. An intense and expanding area of research is focused on discovering other short-term or easily achievable interventions that can have long-lasting beneficial effects," the researchers wrote.
The results of the rodent studies also have implications for human health. "Our findings highlight pregnancy as a sensitive period when positive lifestyle interventions could have significant and long-lasting beneficial effects on offspring metabolism and disease risk," wrote the research team.

Women who have their last baby after 35 are mentally sharper in old age

A new study has found that women have better brainpower after menopause if they had their last baby after age 35, used hormonal contraceptives for more than 10 years or began their menstrual cycle before turning 13.

This is the first study to investigate the association between age at last pregnancy, which can be a marker of a later surge of pregnancy-related hormones, and cognitive function in later life, said Roksana Karim, lead author of the study and assistant professor of clinical preventive medicine at the Keck School of Medicine of USC.

"Based on the findings, we would certainly not recommend that women wait until they're 35 to close their family, but the study provides strong evidence that there is a positive association between later age at last pregnancy and late-life cognition."

Postmenopausal women who had their last pregnancy after 35 had better verbal memory. Those who had their first pregnancy when they were 24 or older had significantly better executive function, which includes attention control, working memory, reasoning and problem solving.

The main hormones at play are estrogen and progesterone. In animal studies, estrogen has a beneficial impact on brain chemistry, function and structure; progesterone is linked with growth and development of brain tissue, Karim said.

The study, published this month in the Journal of the American Geriatrics Society, includes 830 women who, on average, were 60 years old. The data was adjusted for age, race and ethnicity, income, and education.

Participants were given a series of tests that included assessments of verbal memory (remembering a list of words or retelling a story after some distraction), psychomotor speed, attention and concentration, planning, visual perception, and memory.

Previous research has shown that many women experience brainpower and memory declines in their postmenopausal years. An outpouring of estrogen and progesterone, especially in later life, appears to be beneficial, Karim said.

Pregnancy, the pill and more hormones

The study found that other reproductive events were also important to later life cognition. More time between first and last period -- longer reproductive life -- proved valuable for executive function.

"Starting your period early means you have higher levels of the female sex hormone being produced by the ovaries," Karim said. "Girls are receiving the optimal levels early, so it's possible that their brain structures are better developed compared to those who are exposed to estrogen levels associated with menstrual cycles at a later age."

Use of the pill or other hormonal contraceptives for at least 10 years was beneficial for verbal memory and critical thinking ability.

"Oral contraceptives maintain and sustain a stable level of sex hormones in our blood stream," Karim said. "Stable is good."

Women who didn't carry their pregnancy to term and those who gave birth to two children had better overall cognitive ability, verbal memory and executive function when compared to women who had only one full-term pregnancy.

"The finding that even incomplete pregnancies are beneficial was novel and surprising," said Wendy Mack, the study's senior author and professor of preventive medicine at the Keck School of Medicine. "In general, our findings are intriguing and are supported by other clinical studies and animal studies."

In humans, however, previous studies have shown that "pregnancy brain" exists, meaning researchers found that pregnant women have poorer verbal memory, word fluency and word-list learning when compared to non-pregnant women.

"The issue is the human studies haven't followed women for the long term," Mack said. "They just looked at women during pregnancy. We are not sure if we can expect to detect a positive estrogen effect at that point, as the many bodily changes and psycho-social stressors during pregnancy also can impact women's cognitive and emotional functions."

Omega-3 supplements can prevent childhood asthma

Taking certain omega-3 fatty acid supplements during pregnancy can reduce the risk of childhood asthma by almost one third, according to a new study from the Copenhagen Prospective Studies on Asthma in Childhood (COPSAC) and the University of Waterloo.

The study, published in the New England Journal of Medicine, found that women who were prescribed 2.4 grams of long-chain omega-3 supplements during the third trimester of pregnancy reduced their children's risk of asthma by 31 per cent. Long-chain omega-3 fatty acids, which include eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are found in cold water fish, and key to regulating human immune response.

"We've long suspected there was a link between the anti-inflammatory properties of long-chain omega-3 fats, the low intakes of omega-3 in Western diets and the rising rates of childhood asthma," said Professor Hans Bisgaard of COPSAC at the Copenhagen University Hospital. "This study proves that they are definitively and significantly related."

The study used rapid analytical techniques developed and performed at the University of Waterloo to measure levels of EPA and DHA in pregnant women's blood. The University of Waterloo is one of a few laboratories in the world equipped to run such tests.

"Measuring the levels of omega-3 fatty acids in blood provides an accurate and precise assessment of nutrient status," said Professor Ken Stark, Canada Research Chair in Nutritional Lipidomics and professor in the Faculty of Applied Health Sciences at Waterloo, who led the testing. "Our labs are uniquely equipped to measure fatty acids quickly, extremely precisely, and in a cost-efficient manner."

The testing also revealed that women with low blood levels of EPA and DHA at the beginning of the study benefitted the most from the supplements. For these women, it reduced their children's relative risk of developing asthma by 54 per cent.

"The proportion of women with low EPA and DHA in their blood is even higher in Canada and the United States as compared with Denmark. So we would expect an even greater reduction in risk among North American populations," said Professor Stark. "Identifying these women and providing them with supplements should be considered a front-line defense to reduce and prevent childhood asthma."

Researchers analyzed blood samples of 695 Danish women at 24 weeks' gestation and one week after delivery. They then monitored the health status of each participating child for five years, which is the age asthma symptoms can be clinically established.

"Asthma and wheezing disorders have more than doubled in Western countries in recent decades," said Professor Bisgaard. "We now have a preventative measure to help bring those numbers down."

Currently, one out of five young children suffer from asthma or a related disorder before school age.

A new study confirms: Pregnant women should avoid liquorice

A new Finnish study supports food recommendations for families with children in that women should avoid consuming large amounts of liquorice during pregnancy. The limit for safe consumption is not known.

In the study, youths that were exposed to large amounts of liquorice in the womb performed less well than others in cognitive reasoning tests carried out by a psychologist. The difference was equivalent to approximately seven IQ points.

Those exposed to liquorice also performed less well in tasks measuring memory capacity, and according to parental estimates, they had more ADHD-type problems than others. With girls, puberty had started earlier and advanced further.

The Glaku study carried out by the University of Helsinki, the National Institute for Health and Welfare and the Helsinki and Uusimaa hospital districts compared 378 youths of about 13 years whose mothers had consumed "large amounts" or "little/no" liquorice during pregnancy. In this study a large amount was defined as over 500 mg and little/no as less than 249 mg glycyrrhizin per week. These cutoffs are not based on health effects. 500 mg glycyrrhizin corresponds on average to 250 g liquorice.

The study report was published in the American Journal of Epidemiology. The first author of the article is Academy Professor Katri Räikkönen from the University of Helsinki.

Researchers suggest that pregnant women and women planning pregnancy should be informed of the harmful effects that products containing glycyrrhizin - such as liquorice and salty liquorice - may have on the fetus.

In Finland, this is already reality. In January 2016, the National Institute for Health and Welfare published food recommendations for families with children, in which liquorice was placed in the 'not recommended' category for pregnant women. According to the recommendations, occasional consumption of small amounts such as a portion of liquorice ice cream or a few liquorice sweets is not dangerous.

Researchers underline that things should be kept in proportion. A large number of Finns have been exposed to glycyrrhizin in the womb. Glycyrrhizin is one of many factors that affect the development of a fetus but it is impossible to say whether it was glycyrrhizin expressly that affected the development of a certain individual.

As a result of animal experiments, the biological mechanism of the effects of liquorice is well known. Glycyrrhizin intensifies the effects of stress hormone cortisol by inhibiting the enzyme that inactivates cortisol. While cortisol is essential to the development of a fetus, it is detrimental in large amounts.

It has long been known that glycyrrhizin causes higher blood pressure and shorter pregnancies in humans, but such long-lasting effects on the fetus have not been proven before.

Aspirin may help prevent pregnancy loss in women with high inflammation

A daily low dose of aspirin may help a subgroup of women, those who have previously lost a pregnancy, to successfully conceive and carry a pregnancy to term, according to an analysis by researchers at the National Institutes of Health. The women who benefited from the aspirin treatment had high levels of C-reactive protein (CRP), a substance in the blood indicating system-wide inflammation, which aspirin is thought to counteract. The study appears in the Journal of Clinical Endocrinology and Metabolism.

Researchers at NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) analyzed data originally obtained from the Effects of Aspirin in Gestation and Reproduction (EAGeR) trial. The trial sought to determine if daily low-dose aspirin could prevent subsequent pregnancy loss among women who had one or two prior losses.

For the current study, researchers classified the women into 3 groups: low CRP (below .70 mg per liter of blood), mid CRP (from .70 to 1.95) and high CRP (at or above 1.95). Women within each group received either daily low-dose aspirin or a placebo. In their analysis, researchers found no significant differences in birth rates between those receiving aspirin and those receiving placebo in both the low CRP and mid CRP groups. For the high CRP group, those taking the placebo had the lowest rate of live birth at 44 percent, while those taking daily aspirin had a live-birth rate of 59 percent — a 35-percent increase. Aspirin also appeared to reduce CRP levels in the high CRP group when measured during weeks 8, 20, and 36 of pregnancy.

The authors concluded that more research is needed to confirm the findings and to examine the potential influence of inflammation in becoming pregnant and maintaining pregnancy.

Higher Dose of Vitamin D May Benefit Pregnant Women

Vitamin D is essential for strong bones and overall health, but the amount our bodies make from sunlight exposure and obtain from foods is not always enough, particularly for pregnant women.

U.S. Department of Agriculture (USDA) and University of California, Davis (UC Davis) scientists have found that a higher dose of vitamin D supplement during pregnancy may reduce inflammation. Their findings were published in the November 2016 issue of The Journal of Nutrition.

The research team included Charles Stephensen, with the USDA-Agricultural Research Service (ARS) Western Human Nutrition Research Center (WHNRC) in Davis, California; Melissa Zerofsky, a former UC Davis doctorate student; and Bryon Jacoby, a maternal fetal medicine specialist affiliated with UC Davis Medical Center. Researchers wanted to find out whether vitamin D intake levels should be higher than those common in prenatal supplements—400 international units (IU).

Severe vitamin D deficiency can contribute to osteoporosis in adults and rickets (a condition of weakened bones) in infants and children. Recent surveys also suggest that vitamin D deficiency affects up to 69 percent of American pregnant women.

Higher vitamin D levels in a person's blood may protect against certain types of cancer, strengthen the immune system, reduce diabetes risk, and play a key role in suppressing inflammation. Reducing inflammation during pregnancy is important because inflammation is associated with high blood pressure, pre-eclampsia, premature delivery and low birthweight, according to Stephensen, research leader at WHNRC's Immunity and Disease Prevention Research Unit.

In the ARS-UC Davis study, healthy women in their first trimester of pregnancy voluntarily consumed different doses of vitamin D daily. They took either a multivitamin supplement containing 400 IU vitamin D and a placebo pill, or a 400 IU vitamin D supplement and an additional 1600 IU vitamin D pill. Blood samples were analyzed for various forms of vitamin D and immune and inflammatory markers. The mothers' blood pressure and infants' birthweight were recorded.

The vitamin D dosage did not affect maternal blood pressure or infant birthweight. However, the higher daily dose, 2000 IU vitamin D, increased circulating vitamin D concentrations relative to the 400 IU per day. Higher blood vitamin D was correlated with lower circulating tumor necrosis factor-α (TNF-α), an immune substance typically associated with inflammation.

The scientists concluded that consuming 2000 IU vitamin D instead of 400 IU each day is more effective at increasing vitamin D status in pregnant women. They also found that higher levels of vitamin D increased the proportion of a specific subset of immune cells with anti-inflammatory properties that may prevent adverse effects of excess inflammation.