Vitamins and infertility: How vitamin deficiency can cause fertility issues in men and women

PCOS in women is aggravated due to Vitamin D deficiency while for men,Vitamin D deficiency has been associated with reduced sperm quality and infertility.

Polycystic ovary syndrome (PCOS) is also related to female reproductive complications, affecting 4%− 20% of women of reproductive age and is also aggravated due to Vitamin D deficiency while for men, vitamin deficiencies can also play an important role in fertility issues where Vitamin D deficiency has been associated with reduced sperm quality and infertility. Fertility issues in India are rising and are getting higher than ever but conceiving a child is a no less than a dream for a woman.

 

Research suggests that adequate levels of Vitamin D are essential for maintaining optimal sperm production and function. In an interview with HT Lifestyle, Dt Reenu Dubey, Consultant Dietician at Motherhood Hospitals in Bangalore's Electronic City, shared, “There are many factors’ one needs to consider and take care that can affect their fertility. One of the most important factors affecting fertility in individuals is Vitamin deficiency.”

She revealed a list of vitamins and how it can affect their fertility -

Vitamin D:

·  Vitamin D deficiency has been linked to various reproductive health issues, including infertility.

·  Research suggests that adequate levels of vitamin D are essential for the production of reproductive hormones in both men and women.

·  Low levels of vitamin D have been associated with decreased sperm motility and lower levels of testosterone in men, while in women, it can disrupt the menstrual cycle and impair ovarian function.

 

Vitamin B12:

·  Vitamin B12 plays a critical role in DNA synthesis and cellular metabolism, which are essential for reproductive health.

·  Deficiency in vitamin B12 has been linked to ovulatory dysfunction and irregular menstrual cycles in women.

·  In men, low levels of vitamin B12 have been associated with decreased sperm count and motility, potentially leading to male infertility.

 

Folic Acid (Vitamin B9):

·  Folic acid is essential for cell division and DNA synthesis, making it crucial for reproductive health and fetal development.

·  In women, inadequate levels of folic acid can lead to neural tube defects in newborns and increase the risk of miscarriage.

·  Additionally, folic acid deficiency has been linked to decreased sperm count and increased sperm abnormalities in men, affecting fertility.

 

Vitamin C:

·  Vitamin C is a powerful antioxidant that helps protect sperm cells from oxidative damage.

·  Low levels of vitamin C have been associated with decreased sperm quality, including reduced sperm motility and increased DNA damage.

·  In women, vitamin C deficiency may lead to impaired ovarian function and reduced fertility.

Bringing her expertise to the same, Dr M Rajini, Consultant Gynecologist at CARE Hospitals in Hyderabad's Banjara Hills, echoed that vitamin deficiencies can indeed have an impact on fertility, although the specific mechanisms can vary depending on the vitamin in question –

 

•Vitamin D: Low levels of vitamin D have been associated with infertility in both men and women. In men, vitamin D deficiency may lead to decreased sperm motility and concentration. In women, it may disrupt the menstrual cycle and interfere with hormone balance, potentially affecting ovulation.

 

•Vitamin C: Vitamin C is an antioxidant that plays a role in sperm health. Deficiency in vitamin C can lead to sperm damage due to increased oxidative stress, potentially reducing sperm count and motility.

 

•Vitamin E: Similar to vitamin C, vitamin E is an antioxidant that helps protect sperm from oxidative damage. Deficiency in vitamin E may lead to decreased sperm quality and fertility issues in men.

 

•Vitamin B12: Vitamin B12 deficiency has been linked to infertility in both men and women. In men, it may affect sperm production and quality. In women, it can disrupt ovulation and menstrual cycles, potentially leading to infertility.

 

•Folic Acid (Vitamin B9): Folic acid is crucial for fetal development and may also play a role in fertility. Deficiency in folic acid has been associated with ovulatory infertility in women and may increase the risk of miscarriage.

 

•Vitamin A: Vitamin A is essential for reproductive health in both men and women. Deficiency in vitamin A may disrupt the production of sex hormones and impair sperm and egg development, potentially leading to fertility issues.

 

•Vitamin B6: Vitamin B6 is involved in hormone regulation and may affect fertility. Deficiency in vitamin B6 can disrupt hormone balance in women, leading to irregular menstrual cycles and difficulty conceiving.

 

It's important to note that while vitamin deficiencies can contribute to fertility issues, they are often just one factor among many. Other factors such as age, overall health, lifestyle factors (such as diet and exercise) and underlying medical conditions can also influence fertility.

https://www.hindustantimes.com/lifestyle/health/vitamins-and-infertility-how-vitamin-deficiency-can-cause-fertility-issues-in-men-and-women-101714119039540.html

 

New study reveals health risks of neotame, a common sugar substitute used in cakes

These findings serve as a timely reminder of the potential health risks associated with artificial sweeteners, urging consumers and regulatory authorities to exercise caution when considering their use in food products.

A recent study has revealed alarming results of the health effects of neotame, a sugar substitute widely used in cakes, soft drinks, and chewing gum. Researchers have discovered that even small amounts of neotame consumption can lead to significant damage to the gut, resulting in various health issues.

Led by Dr Havovi Chichger, the study highlights the detrimental impact of neotame on intestinal health. Despite being marketed as a healthier alternative to sugar, neotame has been linked to the onset of irritable bowel syndrome, insulin resistance, and even sepsis, a life-threatening condition responsible for numerous fatalities annually in Britain.

The study underscores concerns surrounding the use of certain artificial sweeteners, including neotame, which have been shown to possess what researchers describe as a "toxic effect" on health.

Dr Chichger stressed the importance of considering the risks associated with sweeteners when incorporating them into food products.

Originally developed in 2002 as a replacement for aspartame, neotame, also known as E961, has gained widespread popularity in recent years, featuring prominently in the ingredients list of various consumer products.

However, researchers warn that neotame poses a significant threat to health due to its ability to disrupt the delicate balance of intestinal bacteria, leading to the deterioration of the gut wall and subsequent illness.

Despite previous safety approvals by the European Food Safety Authority (EFSA) in 2010, concerns persist regarding the long-term effects of neotame consumption. Dr Chichger reveals that EFSA is currently reassessing the safety of neotame, highlighting the need for evidence-based risk assessments to ensure consumer safety.

These findings serve as a timely reminder of the potential health risks associated with artificial sweeteners, urging consumers and regulatory authorities to exercise caution when considering their use in food products. As the debate surrounding the safety of neotame continues, further research is imperative to elucidate its full impact on human health.

https://www.wionews.com/world/new-study-reveals-health-risks-of-neotame-a-common-sugar-substitute-714930

Botox row in the US: When can a procedure go wrong?

Dr Pragya Punj, Consultant, Dermatology and Cosmetology, Marengo Asia Hospitals, Gurugram, on what to know before you decide on a treatment

 Botox can go wrong through improper injection techniques.

Recent reports of women in the US falling ill across 11 states after receiving botox injections highlight the potential dangers associated with improperly administered cosmetic procedures and the contents of the shots they are taking. Which is why it is important to consider botox with a dermatologist in a clinical setting, not in a salon.

 

IS BOTOX SAFE?

Botox, a popular treatment for reducing wrinkles and fine lines by paralysing the muscles and nerves with a neurotoxin called botulinum toxin, is generally considered safe. This is only when it is administered by qualified healthcare professionals in appropriate medical settings. However, when the injections are performed by untrained individuals or in a non-medical environment such as homes or spas, the risks of adverse reactions and complications significantly increase.

 

WHEN CAN IT GO WRONG?

Botox can go wrong through improper injection techniques. Its injections require precise placement in specific facial muscles to achieve the desired cosmetic results. When administered incorrectly, the botulinum toxin contained in Botox can spread beyond the targeted area, leading to unintended muscle paralysis, drooping eyelids, or asymmetrical facial expressions. Additionally, injecting Botox into the wrong muscle groups can result in undesirable side effects such as difficulty speaking, swallowing, or breathing.

Another risk factor for adverse outcomes with Botox is the use of counterfeit or diluted products. In unregulated settings, individuals may purchase Botox from unreliable sources or receive counterfeit products that contain unknown ingredients or improper concentrations of the toxin. Using counterfeit or diluted Botox increases the likelihood of ineffective treatment outcomes, adverse reactions and serious complications. The percentage of the concentration of botulinum toxin matters as higher levels could seriously damage your health.

 

RISK FACTORS FOR INFECTION

Furthermore, inadequate sterilisation procedures and poor hygiene practices in non-medical settings pose significant risks of infection and other complications. Sterile medical equipment and aseptic techniques are essential for preventing bacterial contamination and reducing the risk of post-injection infections. In non-clinical settings, you can be at a heightened risk of developing infections at the injection site, including abscesses, cellulitis or even systemic infections. You could even develop an allergic reaction.

 

Qualified healthcare professionals typically conduct thorough medical evaluations and allergy assessment before administering botox injections to identify any contraindications or potential risks for patients. In contrast, unlicensed individuals or beauty salons may overlook important medical history factors or fail to recognize signs of adverse reactions, putting patients’ health and safety at risk. The obvious signs of a mishandled procedure include blurry vision, drooping eyelids, difficulty swallowing, breathing and muscle weakness.

 

On average, the effects of botox are visible in a fortnight and may last about three to four months. A second procedure may be recommended at that time. Eventually, however, your muscles may train themselves to contract less. As a result, treatments can be spaced out over longer periods of time. Your dermatologist will be the best guide.

https://indianexpress.com/article/health-wellness/botox-row-us-procedure-wrong-9291713/

Vitamin D may balance gut microbiome to give cancer immunotherapy a boost

A new study investigates vitamin D’s effect on the gut microbiome and its potential to help cancer immunotherapy work better.

• Over the past few years, researchers have focused on using vitamin D to prevent and treat different cancers.
• Previous research has looked at using vitamin D in conjunction with cancer immunotherapy.
• Researchers from The University of Manchester have found that vitamin D helps balance the gut microbiome, improving the way cancer immunotherapy treatments work via a mouse model.

Over the past few years, several studies have focused on using vitamin D to prevent and treat different types of cancers, including prostate, skin, breast, and bowel cancers.

Previous research has also linked high vitamin D levels to a decreased risk of developing cancer and a reduced cancer mortality rate.

Scientists have also examined the use of vitamin D in conjunction with a newer type of cancer treatment called immunotherapy.

Now researchers from the Cancer Research UK Manchester Institute at The University of Manchester in the U.K. have found that vitamin D helps balance the gut microbiome, improving the way cancer immunotherapy treatments work, via a mouse model.

The study was recently published in the journal Science.

Using immunotherapy to fight cancer 

Immunotherapy is a type of treatment that uses the body’s immune system to help improve its ability to fight cancer.

Different types of immunotherapy treatments include monoclonal antibodies, immune checkpoint inhibitors, immune system modulators, cancer vaccines, and adoptive cell therapies like CAR T-cell therapy.

Over the years, the U.S. FDA has approved several immunotherapy treatments for different types of cancers, with more being added over time.

“Immunotherapy reinvigorates the body’s immune system to attack cancer cells,” Evangelos Giampazolias, PhD, group leader of the Cancer Immunosurveillance Group at the Cancer Research UK Manchester Institute, the University of Manchester and lead author of this study, explained to Medical News Today.

“Immunotherapy has revolutionized the treatment of one of the deadliest forms of cancer, metastatic melanoma, and now is approved as a forefront treatment in a wide range of malignancies including those of kidney and lung,” Giampazolias said.

“However, not all patients respond equally well to this therapy, and only a small group experience long-lasting (benefits),” Giampazolias continued. “Therefore, understanding when and how our immune system identifies malignant cells as a threat is critical for designing therapies that boost its ability to eliminate cancer,” he added.

How does vitamin D affect gut health and cancer treatment?

Giampazolias said that he and his colleagues were intrigued by the fact that the cancer-protective role of vitamin D was absent in mice treated with antibiotics or raised in sterile environments without any living microorganisms.

“Based on these (findings) we hypothesized that vitamin D promotes cancer immunity by influencing the communities of ‘friendly’ microorganisms that live inside the animals, known as (the) microbiome.

We found that vitamin D affects the cells lining the intestine, causing an increase in the levels of a bacteria called Bacteroides fragilis.”– Evangelos Giampazolias, PhD

According to Giampazolias, Bacteroides fragilis is a member of a larger community of microorganisms inhabiting the intestines of mice and humans.

“To determine if the bacteria alone could improve immunity to cancer, mice on a diet containing standard levels of vitamin D were given Bacteroides fragilis,” Giampazolias said. “These mice showed improved ability to resist tumor growth. However, this effect was not observed when the mice were given (a) diet deficient in vitamin D.”

“It is still unclear how Bacteroides fragilis (promotes) anti-cancer immunity but overall, our findings highlight an unprecedented link between vitamin D and gut microbiome that influences immune responses to cancer in mice,” he continued. “Further work is warranted to confirm a possible link between vitamin D and cancer immunity in humans.”

Potential new avenues for improving cancer treatment

After reviewing this study, Anton Bilchik, MD, PhD, surgical oncologist, chief of medicine, and director of the Gastrointestinal and Hepatobiliary Program at Providence Saint John’s Cancer Institute in Santa Monica, CA, told MNT this is a very important study because while doctors have known that vitamin D is important in preventing cancers, the mechanism has been unclear.

Bilchik noted:

“This is one of the first studies to suggest that vitamin D influences a bacteria within our body Bacteroides, which then influences the immune system to reduce the chance of getting cancer. But even more important, demonstrates that immunotherapy is likely to be more effective in the presence of vitamin D. So these are completely novel mechanisms that have been described.”

MNT also spoke with Shama Farooq, MD, MBBS, a neuro-oncologist at Hackensack Meridian Neuroscience Institute at Jersey Shore University Medical Center and assistant professor in the Department of Neurology at Hackensack Meridian School of Medicine in New Jersey.

Farooq said these findings suggest a potential link between vitamin D levels, the microbiome, and cancer immunity, offering potential new avenues for improving cancer treatment and prevention strategies:

“Continued research into enhancing the body’s immunity and optimizing immunotherapy is crucial because cancer is a complex disease with diverse mechanisms of evasion. By exploring new ways to boost the immune system’s ability to recognize and destroy cancer cells, researchers can develop more effective and targeted treatments, ultimately improving patient outcomes and survival rates.”

How much vitamin D is needed to help lower cancer risk? 

Based on this research, readers may wonder if they should make sure their vitamin D levels are correct to help potentially lower their cancer risk.

Bilchik said it’s important for vitamin D levels to be within the normal range, not only for perhaps the prevention of cancer but also because it plays a very important role in bone density, reduction in fractures, and reducing the chance of osteoporosis.

“Vitamin D plays many important roles and despite the fact that vitamin D is easily available through plants, meat, (and the) sun, it’s surprising how many people are vitamin D deficient,” he added.

According to the U.S. National Institutes of Health, levels of 50 nanomoles per liter of vitamin D or above are the healthy range for bone and overall health for most people. Levels below 30 nanomoles per liter or above 125 nanomoles per liter may cause health issues.

“Based on this study, readers should consider ensuring their vitamin D levels are adequate as part of a comprehensive approach to potentially lowering their risk of cancer,” Farooq said. “While more research is needed to fully understand the relationship, maintaining optimal levels of vitamin D is generally beneficial for overall health and may contribute to reducing cancer risk.”

https://www.medicalnewstoday.com/articles/vitamin-d-balances-gut-microbiome-to-improve-cancer-immunotherapy#How-much-vitamin-D-is-needed-to-help-lower-cancer-risk?

Dietary interventions better than medication for IBS management

According to a new study, dietary interventions work better than medication when it comes to managing IBS symptoms.

• Irritable bowel syndrome (IBS) is a prevalent gastrointestinal condition, estimated to affect about one in 10 people globally.
• A new study suggests that dietary interventions may be more effective in reducing IBS symptoms than medical treatments.
• All options showed meaningful symptom improvements, but experts agree that sustained dietary changes are key to managing IBS.

A new study suggests that dietary interventions may be more effective than medication for managing symptoms of irritable bowel syndrome (IBS).

IBS is a chronic gastrointestinal condition affecting an estimated 10% of the global population, making it one of the most common disorders related to gut-brain interactions.

In a first-of-its-kind study, researchers at Sahlgrenska University Hospital in Gothenburg, Sweden, compared the effectiveness of two diet-based treatments and one pharmaceutical treatment in adults with moderate to severe IBS symptoms.

After 4 weeks, both diets and medical intervention significantly reduced symptom severity, with diets outperforming the medical option, and a low FODMAP diet combined with traditional IBS dietary advice being most effective.

A low FODMAP diet contains foods that are low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols, hence its name. This type of diet is often associated with better gastrointestinal health.

In the current study, 6 months after the diet groups had partially resumed normal eating patterns, the majority still reported clinically meaningful symptom improvement.

These findings appeared in The Lancet Gastroenterology & Hepatology.

Dietary interventions vs. medical treatment for IBS

This single-center, single-blind, randomized controlled trial was conducted in a specialized outpatient clinic for disorders of gut-brain interactions.

The study’s 294 participants were predominantly women (82%) with an average age of 38 and moderate-to-severe IBS.

Included participants scored 175 or higher using the IBS Severity Scoring System (IBS-SSS)—measuring abdominal pain frequency and intensity, bloating, satisfaction with bowel habits, and quality of life related to IBS—and had no other serious diseases or food allergies.

They were randomly assigned into three groups:

• a low FODMAP diet coupled with traditional IBS dietary advice from the United Kingdom’s National Institute for Health and Care Excellence (NICE)
• a high-fiber, low-carbohydrate diet with an average carbohydrate intake of 50 grams (g) per day
• pharmaceutical treatment tailored to their specific IBS symptoms.

Participants were unaware of their diet types, but those in the medication group knew their treatment.

A study dietitian informed the diet groups about their diets without revealing diet names or labeling foods as low in FODMAPs or carbohydrates.

After the initial 4-week intervention, the diet groups were advised on how to proceed for six months, including reintroducing FODMAPs for some, while medication group members were offered nutritional guidance alongside their ongoing treatment.

A reduction in IBS-SSS scores was the primary measure of the interventions’ success.

Low FODMAP diet may be best for IBS management

Within the study, high completion rates were observed, with 90% or more of participants finishing the 4-week interventions across all groups.

Following the 4-week intervention, each group recorded a significant decrease in IBS symptoms, as indicated by a drop of 50 points or more in IBS-SSS scores.

The most notable improvement was in the group following a low FODMAP diet and traditional dietary advice (76%), followed by the low-carbohydrate group (71%) and the medication group, which showed the least but still significant improvement (58%).

All groups experienced substantial improvements in quality of life, with fewer physical, anxiety, and depressive symptoms reported.

Despite partially returning to their normal diets during the 6-month follow-up, 68% in the low FODMAP and traditional advice group and 60% in the low-carbohydrate group continued experiencing significant symptom relief, indicating potential long-term benefits.

How low FODMAP and low-carb diets may improve IBS symptoms

The traditional dietary recommendations that were given in the study included consuming regular meals and snacks, sitting during meals, chewing foods thoroughly, and limiting common IBS symptom triggers like coffee, carbonated drinks, alcohol, fatty foods, and spicy foods.

These recommendations were integrated with low-FODMAP food consumption, including foods like rice, potatoes, quinoa, gluten-free bread, vegetables, and fruits, along with low-fat, lactose-free dairy products, fish and seafood, and plant-based proteins.

This combined diet intervention resulted in superior IBS outcomes in the present study.

Alyssa Simpson RDN, CGN, CLT, a registered dietitian and certified gastrointestinal nutritionist, who was not involved in the study, explained why the low FODMAP diet, in particular, is so helpful for those with IBS:

“The low FODMAP diet reduces fermentable carbohydrates that cause gas, bloating, and discomfort in IBS, while also decreasing foods that draw water into the intestines, improving stool consistency. Reducing fermentable carbohydrates in [the] diet may shift the balance of bacteria towards those that thrive on non-fermentable substrates, potentially improving symptoms of IBS.”

She also described how the second best option in the study, a fiber-rich, low-carb diet, could benefit IBS.

Unlike diets high in refined carbs and added sugars, a high-fiber, low-carb diet “may help promote a healthier balance of gut bacteria, which could positively impact IBS symptoms,” she said.

Similar to a low FODMAP diet, “a low-carbohydrate diet may alter the gut microbiota by reducing the availability of carbohydrates for fermentation, favoring the growth of bacteria that metabolize proteins and fats.”

Simpson noted that medications for IBS can indirectly affect the gut microbiome by positively impacting gastrointestinal function and symptoms.

However, certain medications, like antibiotics, can disrupt the balance of gut bacteria, leading to potentially harmful effects, she cautioned.

Dietary changes remain key for IBS treatment

The present study is the first to test a combined low FODMAP and traditional IBS diet, assess a low-carb diet’s effectiveness for IBS, and compare these dietary approaches to standard medical treatments.

Kiran Campbell, a registered dietitian not involved in the study, highlighted that “all three interventions in the study showed improvements in quality of life, anxiety and depression symptoms, and non-gastrointestinal somatic symptoms — like weakness, fatigue, dizziness, etc.”

While all participants in this study experienced benefits, this study had a limited duration, and they were under observation while receiving treatments, so it is possible participants reported improvements in part due to their awareness of being studied.

Still, recent research supports this study’s findings, indicating that low FODMAP and traditional IBS diets outperform other dietary interventions in easing IBS symptoms.

Campbell suggested that in addition to the better outcomes, there are potential long-term benefits of using dietary interventions over medications as a first-line treatment for IBS.

She said these include “improving a patient’s understanding of nutrition and helping them remove barriers to lifelong healthy eating,” as well as potentially helping patients pinpoint specific foods that are causing GI distress.

“In some patients, resolving [gastrointestinal] issues may be as simple as avoiding certain types of sugars (FODMAPS). If pharmacological approaches are used as a first-line of defense these patients would otherwise never know where the issue is originating from. Dietary approaches to managing IBS are a great way to rule out food causes [of] abdominal issues.”— Kiran Campbell, RDN

Individualized IBS care is crucial

To optimize the management of IBS symptoms through dietary interventions, Simpson and Campbell agreed the ultimate goal is to minimize unnecessary restrictions and focus only on eliminating specific trigger foods.

Simpson and Campbell noted that by identifying and avoiding only the foods that aggravate symptoms, patients can achieve a balanced diet, reduce the risk of nutritional deficiencies, and maintain a healthier gut microbiome, contributing to overall quality of life.

They highly recommend working with a registered dietitian for a tailored approach to ensure a diet that is nutritionally adequate, varied, and as unrestricted as possible, facilitating long-term maintenance and well-being.

Ultimately, the experts both emphasized the need for more research into the effects of interventions on nutritional status and the gut microbiome to improve IBS management strategies.

https://www.medicalnewstoday.com/articles/dietary-interventions-better-than-medication-for-ibs-management#Low-FODMAP-diet-may-be-best-for-IBS-management

Human brains are getting bigger: Could this lead to lower dementia risk?

The average human brain has been growing over the last century, according to research.

• Dementia is a growing problem worldwide, with numbers predicted to almost triple over the next 30 years.
• The rise is generally attributed to the growing and aging population, but lifestyle can also contribute.
• However, a new study suggests there may be some good news in the field of dementia.
• It found that people’s brains have been getting larger over the past 100 years, and this increased brain reserve could, potentially, reduce the risk of age-related dementias.

As healthy people get older, the brain decreases slightly in size. However, in people with dementia, as nerve cells are damaged and die, many regions of the brain shrink, a process known as brain atrophy. So, could a larger brain help reduce a person’s risk of dementia?

A new study, from UC Davis Health, has suggested that it might. Researchers found that people born in the 1970s had brains that were, on average, 6.6% larger than those of people born in the 1930s. They suggest that larger brain size means increased brain reserve — which may reduce the risk of age-related dementias.

The study is published in JAMA Neurology.

“While these newly published results add to the body of literature on brain size and changes over time, this study was largely conducted in healthy, well-educated, non-Hispanic White individuals, and so [these findings] are not necessarily generalizable to other groups or individuals.”— Ozama Ismail, PhD, Alzheimer’s Association director of scientific programs, who was not involved in the study.

Dementia’s effects on the brain

Currently, around 58 million people worldwide have dementia, and that number is projected to reach 152.8 million by 2050.

Although some memory loss is a natural part of aging, dementia is not. Dementia describes a range of diseases, with the most common, being Alzheimer’s disease, causing 60-80% of cases. Others include vascular dementia, Lewy body dementia (which may be associated with Parkinson’s disease), frontotemporal dementia, and mixed dementia.

Symptoms of dementia, which worsen over time, may include:

• memory problems
• asking the same question repeatedly
• difficulty finding or understanding words
• feeling confused in unfamiliar environments
• problems dealing with money and numbers
• anxiety and withdrawal
• difficulty planning and carrying out tasks
• mood, personality and behavior changes
• sleep disturbances
• obsessive tendencies

In all types of dementia, as brain cells are damaged and die, there is some degree of brain shrinkage, with this being particularly pronounced in Alzheimer’s disease and vascular dementia.

Human brain sizes are increasing

This study looked at participants in the Framingham Heart Study (FHS). This long-term study has followed 15,000 individuals for more than 75 years.

Of the FHS cohort, 3,226 people had two MRI scans that were suitable for this study. Of them, 1,706 (53%) were women, and 1,520 (47%) were men. The scans measured intracranial volume (ICV), cortical gray matter, cerebral white matter, hippocampal volume, cortical surface area, and cortical thickness measures.

The participants were all born between 1930 and 1970, with the median decade of birth being the 1950s. People born in the 1970s were, on average, 1.6 inches taller than those born in the 1930s, so the researchers adjusted for this when comparing brain measurements.

People born in the 1970s had greater brain volumes than those born in the 1930s.

They had a 6.6% greater ICV, 7.7% more white matter, 2.2% more cortical gray matter, 5.7% greater hippocampal volume, and 14.9% larger cortical surface area. The one measure that had decreased was cortical thickness, which was 20.9% lower. These differences remained significant when the researchers adjusted for height differences.

“The decade someone is born appears to impact brain size and potentially long-term brain health,” said Charles DeCarli, MD, first author of the study, distinguished professor of neurology, and director of the UC Davis Alzheimer’s Disease Research Center in a press release.

“Genetics plays a major role in determining brain size, but our findings indicate external influences — such as health, social, cultural and educational factors — may also play a role,” he said.

“Larger brain structures like those observed in our study may reflect improved brain development and improved brain health. A larger brain structure represents a larger brain reserve and may buffer the late-life effects of age-related brain diseases like Alzheimer’s and related dementias.”— Charles DeCarli, MD

Larger brain size may indicate lower dementia risk

Previous studies have suggested that larger brain volume protects against the effects of dementia pathology, arguing that those with a greater head circumference can endure a greater degree of damage before they start to show cognitive impairment.

This ‘brain reserve hypothesis’ suggests that a larger brain volume, with more neurons and synaptic connections, could provide protection against cognitive decline from brain atrophy. Experts use ICV on MRI and head circumference as indicators of brain volume.

However, this observed effect could be due to other factors, as Ismail told Medical News Today:

“Larger brain volumes may be beneficial in maintaining resilience to cognitive decline and dementia, but many other factors can contribute to resilience, including genetics, environment, socioeconomic status, education, and active vs. sedentary lifestyle.”

Other studies have stressed that cognitive reserve — how well the brain functions — is more important than actual brain size in relation to dementia risk. People with a higher cognitive reserve tend to show dementia symptoms later, but then decline faster once symptoms become evident.

The researchers in this study suggest that the increase in brain volumes over the four birth decades in their study could predict a lower risk of dementia in people born later in the FHS.

Call for more diverse studies

The researchers acknowledge that their study cohort was predominantly non-Hispanic White, healthy, and well-educated, so not representative of the general population of the United States. However, they emphasize that the strengths of the study include the fact that it has followed 3 generations, spanning more than 80 years of births.

Ismail called for further studies that include a greater diversity of people:

“More diversity in research populations is needed before conclusions can be made about changes in brain size over generations and the influence it may have on cognition, resilience, and dementia risk.”

“This is particularly important given the known sociocultural and health disparities that exist in underrepresented populations,” he added.

The Alzheimer’s Association’s U.S. Study to Protect Brain Health Through Lifestyle Intervention to Reduce Risk (U.S. POINTER), which should publish results next year, aims to help address this gap in the research, as Ismail told MNT:

“In the U.S. POINTER Study, more than 2,000 volunteer older adults who are at increased risk for cognitive decline are enrolled and will be followed for two years. Nearly 30% of current participants are from populations historically underrepresented in Alzheimer’s/dementia research.”

https://www.medicalnewstoday.com/articles/human-brains-are-getting-larger-could-this-mean-lower-dementia-risk#Call-for-more-diverse-studies