Every kid from a small family has probably felt sorry for themselves at one time or another for not having loads of brother and sisters. From the outside looking in, there's a lot to envy about families that have enough kids to field their own baseball game, produce complex harmonies a la "The Sound of Music," or put on a play without casting stuffed animals in major roles.
But a new study shows there are convincing reasons not to romanticise large families. A recently published paper from three economists that looks at 26 years of data on parents and children suggests that with every additional kid born, the other siblings are more likely to suffer from lower cognitive abilities and more behavioral issues, and have worse outcomes later in life.
The paper builds on older research that claims that families face a trade-off between the quantity of kids they have and the "quality" of each kid -- an awkward term that refers to things like how much education the child receives, whether they are employed when they grow up, and whether they end up with a criminal record. The research also supports now-popular ideas about early childhood development, that the time and resources that parents devote to young kids have lifelong impacts.
The economists -- Chinhui Juhn, Yona Rubinstein and C. Andrew Zuppann -- drew on a large data set from the National Longitudinal Survey of Youth in 1979, which asked families a ton of questions about their children's math and reading abilities, behavioral issues, and home environments -- such as how often parents read to children or help them with their homework.
The researchers analysed how older siblings performed before and after a younger sibling was born. They found that their measure of parental investment in older kids -- represented by things like how often families eat meals together, how often parents show kids affection and how many books each child has -- fell by 3 percentage points after a young child is born, while cognitive scores fell by 2.8 percentage points and behavioral problems increased.
The effects also differed depending on the older kid's gender, Juhn and her co-authors found. Girls who gained younger siblings were more likely to see their reading and math scores suffer, while boys were more likely to have behavioral issues.
Health news in pictures
Health news in pictures
1/25 Most child antidepressants are ineffective and can lead to suicidal thoughts
The majority of antidepressants are ineffective and may be unsafe, for children and teenager with major depression, experts have warned. In what is the most comprehensive comparison of 14 commonly prescribed antidepressant drugs to date, researchers found that only one brand was more effective at relieving symptoms of depression than a placebo. Another popular drug, venlafaxine, was shown increase the risk users engaging in suicidal thoughts and attempts at suicide
2/25 'Universal cancer vaccine’ breakthrough claimed by experts
Scientists have taken a “very positive step” towards creating a universal vaccine against cancer that makes the body’s immune system attack tumours as if they were a virus, experts have said. Writing in Nature, an international team of researchers described how they had taken pieces of cancer’s genetic RNA code, put them into tiny nanoparticles of fat and then injected the mixture into the bloodstreams of three patients in the advanced stages of the disease. The patients' immune systems responded by producing "killer" T-cells designed to attack cancer. The vaccine was also found to be effective in fighting “aggressively growing” tumours in mice, according to researchers, who were led by Professor Ugur Sahin from Johannes Gutenberg University in Germany
3/25 Green tea could be used to treat brain issues caused by Down’s Syndrome
A compound found in green tea could improve the cognitive abilities of those with Down’s syndrome, a team of scientists has discovered. Researchers found epigallocatechin gallate – which is especially present in green tea but can also be found in white and black teas – combined with cognitive stimulation, improved visual memory and led to more adaptive behaviour. Dr Rafael de la Torre, who led the year-long clinical trial along with Dr Mara Dierrssen, said: “The results suggest that individuals who received treatment with the green tea compound, together with the cognitive stimulation protocol, had better scores in their cognitive capacities”
4/25 New online test predicts skin cancer risk
Health experts have created a new online tool which can predict a person’s risk of developing a common form of skin cancer. The tool uses the results of a 10-question-quiz to estimate the chance of a person aged 40 or over of having non-melanoma skin cancers within three years. Factors including the age, gender, smoking status, skin colour, tanning ability, freckling tendency, and other aspects of medical history are covered by the quiz
5/25 Multiple Sclerosis stem cell treatment 'helps patients walk again'
A new treatment for multiple sclerosis (MS) has enabled some patients to walk again by “rebooting” their immune systems. As part of a clinical trial at Sheffield's Royal Hallamshire Hospital involving around 20 patients, scientists used stem cells to carry out a bone marrow transplant. The method known as an autologous haematopoietic stem cell transplant (HSCT) works by using chemotherapy to destroy the area of the immune system which causes MS
6/25 Dementia patients left without painkillers and handcuffed to bed
Dementia patients experience a ‘shocking’ variation in the quality of hospital care they receive across England, a charity has warned. Staff using excessive force and not giving dementia patients the correct pain medication were among the findings outlined in a new report by The Alzheimer’s Society, to coincide with the launch of Fix Dementia Care campaign
7/25 Cancer risk 'increased' by drinking more than one glass of wine or pint of beer per day
Drinking more than one glass of wine or pint of beer a day increases the risk of developing cancer, according to medical experts. New guidelines for alcohol consumption by the UK published by chief medical officers warn that drinking any level of alcohol has been linked to a range of different cancers. The evidence from the Committee on Carcinogenicity (COC) overturns the oft-held view that a glass of red wine can have significant medical benefits for both men and women
8/25 Vaping 'no better' than smoking regular cigarettes
Vaping could be “no better” than smoking regular cigarettes and may be linked to cancer, scientists have found. The study which showed that vapour from e-cigarettes can damage or kill human cells was publsihed as the devices are to be rolled out by UK public health officials as an aid to quit smoking from 2016. An estimated 2.6 million people in the UK currently use e-cigarettes
9/25 Rat-bite fever
A teenager was hospitalised and left unable to move after she developed the rare rat-bite fever disease from her pet rodents which lived in her bedroom. The teenager, who has not been named, was taken to hospital after she complained of a pain in her right hip and lower back which later made her immobile, according to the online medical journal BMJ Case Reports. She suffered for two weeks with an intermittent fever, nausea and vomiting and had a pink rash on her hands and feet. The teenager, who had numerous pets including a dog, cat, horse and three pet rats, has since made a full recovery after undergoing a course of antibiotics. Blood tests showed that she was infected with for streptobacillus moniliformis – the most common cause of rat-bite fever. One of her three pet rats lay dead in her room for three weeks before her symptoms showed
10/25 Taking antidepressants in pregnancy ‘could double the risk of autism in toddlers’
Taking antidepressants during pregnancy could almost double the risk of a child being diagnosed with autism in the first years of life, a major study of nearly 150,000 pregnancies has suggested. Researchers have found a link between women in the later stages of pregnancy who were prescribed one of the most common types of antidepressant drugs, and autism diagnosed in children under seven years of age
11/25 Warning over Calpol
Parents have been warned that giving children paracetamol-based medicines such as Calpol and Disprol too often could lead to serious health issues later in life. Leading paediatrician and professor of general paediatrics at University College London, Alastair Sutcliffe, said parents were overusing paracetamol to treat mild fevers. As a result, the risk of developing asthma, as well as kidney, heart and liver damage is heightened
12/25 Fat loss from pancreas 'can reverse' effects of type-2 diabetes
Less than half a teaspoon of fat is all that it takes to turn someone into a type-2 diabetic according to a study that could overturn conventional wisdom on a disease affecting nearly 3 million people in Britain. Researchers have found it is not so much the overall body fat that is important in determining the onset of type-2 diabetes but the small amount of fat deposited in the pancreas, the endocrine organ responsible for insulin production
13/25 Potatoes reduce risk of stomach cancer
Scientists have found people who eat large amounts of white vegetables were a third less likely to contract stomach cancer. The study, undertaken by Chinese scientists at Zhejiang University, found eating cauliflower, potatoes and onions reduces the chance of contracting stomach cancer but that beer, spirits, salt and preserved foods increased a person’s risk of the cancer
14/25 Connections between brain cells destroyed in early stages of Alzheimer’s disease
Scientists have pinpointed how connections in the brain are destroyed in the early stages of Alzheimer’s disease, in a study which it is hoped will help in the development of treatments for the debilitating condition. At the early stages of the development of Alzheimer’s disease the synapses – which connect the neurons in the brain – are destroyed, according to researchers at the University of New South Wales, Australia. The synapses are vital for brain function, particularly learning and forming memories
15/25 Sugar tax
The Government should introduce a sugar tax to prevent an “obesity crisis” from crippling the NHS, a senior Conservative MP and former health minister has said. Dr Dan Poulter believes that the case for increased taxes on unhealthy sugary products was “increasingly compelling”
16/25 Cancer breakthrough offers new hope for survivors rendered infertile by chemotherapy
A potentially “phenomenal” scientific breakthrough has offered fresh hope to cancer patients rendered infertile by chemotherapy. For the first time, researchers managed to restore ovaries in mice affected by chemotherapy so that they were able to have offspring. The scientists now plan to begin clinical trials to see if the technique, which involves the use of stem cells, will also work in humans by using umbilical cord material and possibly stem cells taken from human embryos, if regulators agree
17/25 Take this NHS test to find out if you have a cancerous mole
An interactive test could help flag up whether you should seek advice from a health professional for one of the most common types of cancer. The test is available on the NHS Choices website and reveals whether you are at risk from the disease and recommends if you should seek help. The mole self-assessment factors in elements such as complexion, the number of times you have been severely sunburnt and whether skin cancer runs in your family. It also quizzes you on the number of moles you have and whether there have been any changes in appearance regarding size, shape and colour
18/25 Health apps approved by NHS 'may put users at risk of identity theft'
Experts have warned that some apps do not adequately protect personal information
19/25 A watchdog has said that care visits must last longer
The National Institute for Health and Care Excellence (Nice) said home help visits of less than 30 minutes were not acceptable unless part of a wider package of support
20/25 Pendle in Lancashire tops list of five most anxious places to live in the UK
Pendle in Lancashire has been named the most anxious place to live in the UK, while people living in Fermanagh and Omagh in Northern Ireland have been found to be the happiest
21/25 Ketamine could be used as anti-depressant
Researchers at the University of Auckland said monitoring the effects of the drug on the brain has revealed neural pathways that could aid the development of fast-acting medications. Ketamine is a synthetic compound used as an off anaesthetic and analgesic drug, but is commonly used illegally as a hallucinogenic party drug. Dr Suresh Muthukumaraswamy, a senior researcher at the university and a member of the institution’s Centre for Brain Research, used the latest technology in brain imaging to investigate what mechanisms ketamine uses to be active in the human brain
22/25 A prosthetic hand that lets people actually feel through
The technology lets paralysed people feel actual sensations when touching objects — including light taps on the mechanical finger — and could be a huge breakthrough for prosthetics, according to its makers. The tool was used to let a 28-year-old man who has been paralysed for more than a decade. While prosthetics have previously been able to be controlled directly from the brain, it is the first time that signals have been successfully sent the other way
23/25 The biggest cause of early death in the world is what you eat
Unhealthy eating has been named as the most common cause of premature death around the globe, new data has revealed. A poor diet – which involves eating too few vegetables, fruits, nuts and grains and too much red meat, salt and sugar - was shown to be a bigger killer than smoking and alcohol
24/25 Scientists develop blood test that estimates how quickly people age
Scientists believe it could be used to predict a person’s risk of developing Alzheimer’s disease as well as the “youthfulness” of donated organs for transplant operations. The test measures the vitality of certain genes which the researchers believe is an accurate indication of a person’s “biological age”, which may be younger or older than their actual chronological age
25/25 Aspirin could help boost therapies that fight cancer
The latest therapies that fight cancer could work better when combined with aspirin, research has suggested. Scientists from the Francis Crick Institute in London say the anti-inflammatory pain killer suppresses a cancer molecule that allows tumours to evade the body’s immune defences. Laboratory tests have shown that skin, breast and bowel cancer cells often generate large amounts of this molecule, called prostaglandin E2 (PGE2). But Aspirin is one of a family of drugs that sends messages to the brain to block production of PGE2 and this means cancer cells can be attacked by the body’s natural defences
The birth of another kid also lowered the overall amount of education that each child received. For each additional child born, the researchers found that the average amount of education the kids in the family received fell by -.13 years. And older children whose parents had twins ended up with nearly half a year less of education than other families.
The research showed that these effects weren’t a temporary side effect of the birth of a younger sibling, but persisted through childhood and into later life -- resulting in lower education, lower earnings, more criminal behavior and more teenage pregnancies.
To figure out why exactly these trends were occurring, the researchers split up "parental investment" into four different factors -- the time parents spent with their kids, the resources (including money, books, clothes, etc.) they devoted to each child, the affection parents gave their kids, and how safe the home environment was -- and investigated each.
They found that the amount of time that parents spend with each kid is the factor that changed the most following the birth of another kid. The other factors didn't change significantly, they said.
Juhn, Rubinstein and Zuppann did find one external factor that appeared to have a big influence on these outcomes -- the cognitive abilities of the mothers.
Mothers in the original data set were also made to take the Armed Force Qualification Test, which is a test the military uses to assess reading, reasoning and other basic abilities. The researchers found that children of mothers who didn't score well on this test saw a much larger drop in cognitive skills when another child arrived.
One plausible explanation is that mothers with higher scores tend to be better educated and wealthier. Indeed, mothers with higher scores were more likely to quit their jobs or reduce the hours they worked after having another kid, while mothers with lower scores were likely to work the same amount -- perhaps because they didn't have the option of quitting their jobs. Compared to those with lower scores, mothers with the high scores, and presumably more education, appeared to face less of a trade-off between the number of kids they had and how much time and resources they could devote to each.
The researchers say this could be partly due to a lack of supportive policies in the United States for mothers and families -- including parental leave and child-care coverage. This could explain why economists have seen a so-called "quantity-quality trade-off" in some countries, but not in others, they write.
For example, one study published in 2005 that looked at families and kids among the entire population of Norway turned up substantially different findings. That study showed only negligible effects from family size on a kid's performance. However, a similar study done in China showed a big effect, with kids in larger families receiving much less schooling, especially in rural areas.
Juhn and her co-authors hypothesise that the discrepancy could be due to different policies in different countries.
Countries like Norway, which have extensive welfare programs, parental leave and other supportive policies for families, and strong public education, might see less of a trade-off for families between the quantity and quality of children, they hypothesizse. But parents in countries like the United States and China, which have a more limited support system for families and lower-income people, might be forced to choose, they say.
© Washington PostReuse content