Saturday, June 15, 2024

Eating small fish whole can prolong life expectancy

 

Peer-Reviewed Publication


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EATING SMALL FISH WHOLE CAN PROLONG LIFE EXPECTANCY, A JAPANESE STUDY FINDS

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CREDIT: CHINATSU KASAHARA

A new study has found evidence linking the intake of small fish, eaten whole, with a reduced risk of all-cause and cancer mortality in Japanese women. Conducted by Dr. Chinatsu Kasahara, Associate Professor Takashi Tamura, and Professor Kenji Wakai at Nagoya University Graduate School of Medicine in Japan, the study highlights the potential life-extending benefits of habitually eating small fish. The findings were published in the journal Public Health Nutrition. 

Japanese people habitually eat small fish, such as whitebait, Atlantic capelin, Japanese smelt, and small dried sardines. Importantly, it is common practice to consume small fish whole, including the head, bones, and organs, which are rich in micronutrients, such as calcium and vitamin A.  

“Previous studies have revealed the protective effect of fish intake on health outcomes, including mortality risks. However, few studies have focused on the effect of the intake of small fish specifically on health outcomes,” said the lead researcher, Dr. Kasahara. “I was interested in this topic because I have had the habit of eating small fish since childhood. I now feed my children these foods.” 

The research team investigated the association between the intake of small fish and mortality risk among Japanese people. The study included 80,802 participants (34,555 men and 46,247 women) aged 35 to 69 years nationwide in Japan. The participants' frequency of the intake of small fish was assessed using a food frequency questionnaire at baseline. The researchers followed them for an average of nine years. During the follow-up period, 2,482 deaths from people included in the study were recorded, with approximately 60% (1,495 deaths) of them being cancer related. 

One of the most striking findings of the study was the significant reduction in all-cause and cancer mortality among women who habitually eat small fish. Women who eat small fish 1-3 times a month, 1-2 times a week, or 3 times or more a week had 0.68, 0.72, and 0.69 times the risk of all-cause mortality, and 0.72, 0.71, and 0.64 times the risk of cancer mortality, compared to those who rarely eat small fish. 

After controlling for factors that can affect mortality risk, such as participants' age, smoking and alcohol consumption habits, BMI, and intake of various nutrients and foods, the researchers found that women in the study who eat small fish frequently were less likely to die from any cause. These findings suggest that incorporating small fish into their daily diet could be a simple but effective strategy to reduce the risk of mortality among women.  

The risk of all-cause and cancer mortality in men showed a similar trend to that in women, although it was not statistically significant. The reasons for the lack of significance in men remain unclear, but the researchers posit that the limited number of male subjects or other factors not measured in the study, such as the portion size of small fish, may also matter. According to the researchers, the difference in the cancer type causing cancer mortality among sexes may be related to a sex-specific association. 

Although acknowledging the need for additional research in other populations and a deeper understanding of the mechanisms involved, Dr. Kasahara is enthusiastic about the results. “While our findings were only among Japanese people, they should also be important for other nationalities,” she said. 

In fact, previous studies have highlighted affordable small fish as a potentially important source of nutrients, especially in developing countries that suffer from severe nutrient deficiency. This study adds to the growing body of evidence supporting the health benefits of dietary practices that include eating small fish. As Dr. Kasahara explained, “Small fish are easy for everyone to eat, and they can be consumed whole, including the head, bones, and organs. Nutrients and physiologically active substances unique to small fish could contribute to maintaining good health. The inverse relationship between the intake of small fish and the mortality risk in women underscores the importance of these nutrient-dense foods in people's diets.” 

 “The habit of eating small fish is usually limited to several coastal or maritime countries, such as Japan,” Associate Professor Tamura said. “However, we suspect that the intake of small fish anywhere may be revealed as a way to prolong life expectancy. Further evidence is necessary to elucidate the potential role of the intake of small fish in mortality risk.” 

Short-term loneliness associated with physical health problems

 

In the wake of the surgeon general’s warning about a loneliness epidemic, a study by Penn State researchers finds social connection may influence physical health and well-being

Loneliness may be harmful to our daily health, according to a new study led by researchers in the Penn State College of Health and Human Development and Center for Healthy Aging focused on understanding the subtleties of loneliness and how variations in daily feelings of loneliness effect short- and long-term well-being. The researchers said the work provides more evidence in support of the 2023 statement made by U.S. Surgeon General Vivek Murthy on the devastating impact of loneliness and isolation on physical health in the country, calling it a public health crisis.

The work, published in the journal Health Psychologyalso brings more attention to different experiences of loneliness, a focus during June 10-16 for Loneliness Awareness Week. 

The long-term health consequences of loneliness and insufficient social connection include a 29% increased risk of heart disease, a 32% increased risk of stroke and a 50% increased risk of developing dementia in older adults, according to the surgeon general. People who frequently feel lonely are also more likely to develop depression and other mental health challenges, compared to people who rarely or never feel lonely.

In the current study, the researchers found that loneliness can lead to negative health symptoms for people even if they do not generally identify as lonely or typically experience loneliness. People who experience more temporary feelings of loneliness or have a lot of variability in their feelings of loneliness are likely to have daily health issues related to loneliness, including general fatigue, headaches and nausea.

The data represents 1,538 participants in the National Study of Daily Experiences (NSDE), one of the studies in the MacArthur Foundation Survey of Midlife in the United States. NSDE is led by David Almeida, professor of human development and family studies at Penn State and senior author on the paper. The current study focuses on loneliness in midlife, using data from respondents between the ages of 35 and 65. Prior research on loneliness largely focuses on adolescents and older adults, the researchers said.

NSDE participants engaged in telephone interviews that assessed their daily stress and mood for eight consecutive days. Respondents were asked to describe any stressful and/or positive situations they encountered and their feelings for each day, including whether they felt lonely and how often. They were also asked if they had physical symptoms that day, including general fatigue or headaches. These assessments were performed twice, 10 years apart. 

From this data, researchers found that when participants were less lonely on average, and on days when loneliness was lower than a person’s average, they had fewer and less severe physical health symptoms. Additionally, participants who were more stable in loneliness across the eight days had less severe physical health symptoms.

“These findings suggest that day-to-day dynamics of loneliness may be crucial in understanding and addressing the health effects of loneliness,” Almeida said. “Increasing feelings of social connection even for one day could result in fewer health symptoms on that day. Such a daily focus offers a manageable and hopeful micro-intervention for individuals living with loneliness.”

Dakota Witzel, a postdoctoral research fellow in the Center for Healthy Aging and the lead author on the paper, said the results suggest that closer attention should be paid to daily, more temporary feelings of loneliness. While sustained loneliness can contribute to the long-term health effects identified in the surgeon general’s advisory, these shorter, more variable instances of loneliness can produce shorter-term negative health symptoms.

“A lot of research is focused on loneliness being a binary trait — either you’re lonely or you’re not. But based on our own anecdotal lives, we know that’s not the case. Some days are worse than others — even some hours,” Witzel said. “If we can understand variations in daily loneliness, we can begin to understand how it affects our daily and long-term health.”


Friday, June 14, 2024

Exploring the safety, efficacy, and bioactivity of herbal medicines


Bridging traditional wisdom and modern science in healthcare


Herbal medicines have been an integral part of traditional healthcare systems worldwide, dating back thousands of years. These natural remedies, rooted in cultural traditions, are now experiencing a resurgence in popularity as the demand for holistic and personalized healthcare grows. This review explores the convergence of traditional wisdom and modern science in the realm of herbal medicines, focusing on their safety, efficacy, and bioactivity in contemporary healthcare settings.

 

The historical context of herbal medicines is rich and varied. In ancient civilizations, such as those in China, India, and Egypt, herbal remedies were central to medical practices. Systems like Ayurveda and Traditional Chinese Medicine (TCM) have long utilized a vast array of herbs for treating various ailments. These traditional practices were based on centuries of observation, experimentation, and documentation, creating a deep reservoir of knowledge. Today, this ancient wisdom is being revisited and scientifically validated, bridging the gap between traditional and modern healthcare.

 

One of the primary concerns with the use of herbal medicines is their safety. Unlike conventional drugs, herbal remedies often contain multiple active ingredients, which can lead to complex interactions within the body. This review meticulously examines the safety profiles of various herbal remedies. It highlights the importance of rigorous scientific scrutiny to identify potential adverse effects and interactions with conventional medications. Standardization of herbal preparations is emphasized to ensure safety, efficacy, and consistency. Case studies and clinical trials are reviewed to provide a comprehensive understanding of the safety concerns associated with herbal medicine use.

 

The therapeutic efficacy of herbal interventions is a critical area of investigation. Historically, the benefits of herbal remedies were supported by anecdotal evidence and traditional practices. However, modern science demands empirical evidence to validate these claims. This review evaluates the efficacy of herbal interventions through the lens of contemporary research. Clinical trials and studies on herbs like turmeric (curcumin), Ginkgo biloba, and garlic are discussed, showcasing their benefits in improving cognitive function, cardiovascular health, metabolic disorders, and more. By comparing historical anecdotes with empirical data, this review provides a balanced perspective on the therapeutic potential of herbal medicines.

 

Understanding the bioactivity and mechanisms of action of herbal compounds is crucial for their integration into modern healthcare. Herbal remedies often contain a myriad of active ingredients that work synergistically to produce therapeutic effects. This review delves into the complex bioactivity of these compounds, explaining how they interact with human physiology. For example, curcumin's anti-inflammatory properties, Ginkgo biloba's neuroprotective effects, and garlic's antimicrobial properties are explored in detail. The pharmacokinetics and pharmacodynamics of these herbs are analyzed to provide a scientific basis for their use in medical treatments.

 

The integration of herbal medicine into modern healthcare presents both opportunities and challenges. This review discusses the potential benefits of incorporating herbal remedies into conventional medical practices. It highlights successful case studies where herbal medicines have been used alongside conventional treatments to enhance patient outcomes. The review also addresses the regulatory and standardization issues that must be overcome to ensure the safe and effective use of herbal remedies. By fostering a dialogue between traditional practitioners and modern scientists, this review advocates for a holistic approach to healthcare that combines the strengths of both systems.

 

In conclusion, the synthesis of traditional wisdom and modern science in the field of herbal medicine holds great promise for advancing healthcare. By critically examining the safety, efficacy, and bioactivity of herbal remedies, this review illuminates the evolving landscape of herbal medicine. The goal is to integrate the best of both worlds, enhancing global well-being through effective, safe, and holistic treatment options. As interest in personalized and holistic healthcare grows, the potential of herbal medicine as a valuable complement to modern healthcare practices becomes increasingly evident.

 

Full text:

https://www.xiahepublishing.com/2835-6357/FIM-2023-00086 

Thursday, June 13, 2024

Depressive symptoms may hasten memory decline in older people

 

Depressive symptoms are linked to subsequent memory decline in older people, while poorer memory is also linked to an increase in depressive symptoms later on, according to a new study led by researchers at UCL and Brighton and Sussex Medical School.

The study, published in JAMA Network Open, looked at 16 years of longitudinal data from 8,268 adults in England with an average age of 64.

The researchers concluded that depression and memory were closely interrelated, with both seeming to affect each other.

Senior author Dr Dorina Cadar, of the UCL Department of Behavioural Science & Health and Brighton and Sussex Medical School, said: “It is known that depression and poor memory often occur together in older people, but what comes first has been unclear.

“Our study shows that the relationship between depression and poor memory cuts both ways, with depressive symptoms preceding memory decline and memory decline linked to subsequent depressive symptoms.

“It also suggests that interventions to reduce depressive symptoms may help to slow down memory decline.”

Lead author Jiamin Yin, who graduated from UCL and is now a doctoral student at the University of Rochester, New York, said: “These findings underscore the importance of monitoring memory changes in older adults with increasing depressive symptoms to identify memory loss early and prevent further worsening of depressive function.

“Conversely, it is also critical to address depressive symptoms among those with memory decline to protect them from developing depression and memory dysfunction.”

The research team suggested that depression might affect memory due to depression-related changes in the brain. These include neurochemical imbalances (e.g. lower levels of serotonin and dopamine), structural changes in regions involved in memory processing, and disruptions to the brain’s ability to re-organise and form new connections.

The team said that memory impairments also might arise from psychological factors such as rumination – that is, repetitive thinking or dwelling on negative feelings.

On the other hand, people experiencing memory lapses or difficulties in retaining new information can lead to frustration, loss of confidence, and feelings of incompetence, which are common triggers for depressive episodes. Memory impairment may also disrupt daily functioning and social interactions, leading to social isolation potentially triggering depressive symptoms.

Dr Cadar added: “Depression can cause changes in brain structures, such as the hippocampus, which is critical for memory formation and retrieval. Chronic stress and high levels of cortisol associated with depression can damage neurons in these areas. However, a further understanding of mechanisms linking memory decline and depression is crucial for developing targeted interventions aimed at improving mood and slowing cognitive decline in individuals with depression and memory impairment.”

For this study, the researchers looked at data from the English Longitudinal Study of Ageing (ELSA), in which a nationally representative population sample in England answers a wide range of questions every two years.

People who started with higher depressive symptoms were more likely to experience faster memory decline later, while those who started with poorer memory were more likely to experience a later increase in depressive symptoms.

In addition, participants who experienced more of an increase in depressive symptoms during the study were more likely to have a steeper memory decline at the same time, and vice versa – those who had a steeper memory decline were more likely to have a sharper increase in depressive symptoms.

The same pattern was not found for verbal fluency. While less verbal fluency was linked to more depressive symptoms at the start of the study, changes in one did not predict later changes in the other.

The researchers accounted for a range of factors that might have affected the results, such as physical activity and life-limiting illness. As an observational study, the researchers noted, it could not establish causality.

People with knee OA unconsciously believe that activity may be dangerous to their condition


 

Knee osteoarthritis (OA) is a common cause of pain and joint stiffness. And while physical activity is known to ease symptoms, only one in 10 people regularly exercise.

 

Understanding what contributes to patients’ inactivity is the focus of a world first study from the University of South Australia. Here, researchers have found that people with knee OA unconsciously believe that activity may be dangerous to their condition, despite medical advice telling them otherwise.

 

The study found that of those surveyed, 69% of people with knee pain had stronger implicit (unconscious) beliefs that exercise was dangerous than the average person without pain.    

 

It’s an interesting finding that not only highlights the conflicted nature of pain and exercise, but also that what people say and what people think, deep down, may be entirely different things.

 

Lead researcher, and UniSA PhD candidate based at SAHMRIBrian Pulling, says the research provides valuable insights for clinicians treating people with knee OA.

 

“Research shows that physical activity is good for people with knee OA, but most people with this condition do not move enough to support joint or general health,” Pulling says.

 

“To understand why people with OA might not be active, research studies typically use questionnaires to assess fear of moving. But unfortunately, questionnaires are limited – what we feel deep down (and how our system naturally reacts to something that is threatening) may be different to what we report. And we still know that many people are avoiding exercise, so we wanted to know why.”

 

To assess this, the researchers developed a tool that can detect and evaluate people’s implicit beliefs about exercise; that is, whether they unconsciously think activity is dangerous for their condition.

 

“We found that that even among those who said they were not fearful about exercise, they held unconscious beliefs that movement was dangerous,” Pulling says.

 

“Our research shows that people have complicated beliefs about exercise, and that they sometimes say one thing if asked directly yet hold a completely different implicit belief.

 

“People are not aware that what they say doesn’t match what they choose on the new task; they are not misrepresenting their beliefs.

 

“This research suggests that to fully understand how someone feels about an activity, we must go beyond just asking directly, because their implicit beliefs can sometimes be a better predictor of actual behaviour than what people report. That’s where our tool is useful.”

 

The online implicit association test presents a series of words and images to which a participant must quickly associate with being either safe or dangerous. The tool intentionally promotes instant responses to avoid deliberation and other influencing factors (such as responding how they think they should respond).

 

Associate Professor Tasha Stanton says that the new tool has the potential to identify a group of people who may have challenges increasing their activity levels and undertaking exercise.

 

“What people say and what people do are often two different things, Assoc Prof Stanton says.

 

“Having access to more accurate and insightful information will help health professionals better support their patients to engage with activity and exercise. It may also open opportunities for pain science education, exposure-based therapy, or cognitive functional therapy…things that would not usually be considered for someone who said that they were not scared to exercise.”

 

Researchers are now looking to see if implicit beliefs are directly associated with behaviour and are asking for people to complete the Implicit Association Test (takes seven minutes). At the end of the test participants are given their results in comparison to the rest of the population.

 

To take the test, please click here: https://unisasurveys.qualtrics.com/jfe/form/SV_0OZKUqzBNtiKGF0

 

Tuesday, June 11, 2024

Physical activity in the evening lowers blood sugar levels

 

New research reveals that moderate to vigorous physical activity in the evening for sedentary adults with overweight and obesity is most beneficial in lowering daily blood sugar levels, according to a study published in Obesity, The Obesity Society’s (TOS) flagship journal.

Experts explain that it has been well established that moderate to vigorous physical activity enhances glucose homeostasis in adults with overweight and obesity who are at higher risk of developing insulin resistance. However, little is known about the optimal timing of moderate to vigorous physical activity to improve daily blood glucose control.

“Our results highlight the importance of the field of precision exercise prescription. In clinical practice, certified sports and medical personnel should consider the optimal timing of the day to enhance the effectiveness of the exercise and physical activity programs they prescribe,” said Jonatan R. Ruiz, PhD, professor of physical activity and health, Department of Physical and Sports Education, Faculty of Sport Sciences-Sport and Health University Research Institute (iMUDS), University of Granada, ibs.Granada and CIBEROBN, Spain. Ruiz is one of two corresponding authors of the study with predoctoral researcher Antonio Clavero-Jimeno from the same research center.

Data for the study was used from baseline examinations from a multi-center randomized controlled trial conducted in Granada and Pamplona, Spain. The aim of the trial was to study the efficacy and feasibility of time-restricted eating on visceral adipose tissue (primary outcome), body composition and cardiometabolic risk factors in adults with overweight and obesity.

A total of 186 adults with an average age of 46 years and a body mass index of 32.9 kg/mwith overweight or obesity participated in the cross-sectional study. The physical activity and glucose patterns of participants were simultaneously monitored over a 14-day period using a triaxial accelerometer worn on the non-dominant wrist and a continuous glucose-monitoring device.

The study’s researchers classified the volume of moderate to vigorous physical activity accumulated for each day. Categories included inactive (if no activity was accumulated), and as ‘morning,’ ‘afternoon’ or ‘evening’ if more than 50% of the moderate to vigorous physical activity minutes for that day were accumulated between 6 a.m. to noon, noon to 6 p.m., 6 p.m. to 12 p.m., or as ‘mixed’ if none of the defined time windows accounted for greater than 50% of the moderate to vigorous physical activity for that day.

Results showed that accumulating greater than 50% of moderate to vigorous physical activity in the evening was associated with lowering day, night and overall blood glucose levels compared with being inactive. This association was stronger in those participants with impaired glucose regulation. The pattern of these associations was similar in both men and women.

“As the field moves towards individualized exercise prescriptions for different chronic conditions, this study now provides additional insights beyond just telling patients to ‘move more,’ but instead to move as often as possible and to prioritize afternoon-to-evening movement when feasible for glucose regulation,” said Renee J. Rogers, PhD, FACSM, senior scientist, Division of Physical Activity and Weight Management, University of Kansas Medical Center. Rogers was not associated with the research.

Nutritional recommendations for patients treated with anti-obesity medications

 

Individuals treated with anti-obesity medications generally experience reduced appetite, which typically leads to reduced food intake. As a result, dietary quality becomes more important because nutritional needs must be met within the context of eating less. To improve this process, medical experts have developed a list of evidence-based nutritional recommendations to assist clinicians treating patients with anti-obesity medications, according to a review published in the journal Obesity, The Obesity Society’s (TOS) flagship journal.


“Our evidence-based review aims to equip clinicians with knowledge and tools to help support optimal nutritional and medical outcomes for their patients treated with anti-obesity medications,” said Eli Lilly and Company Executive Director of Global Medical Affairs—Obesity Lisa M. Neff. Neff is the corresponding author of the review paper.

In the review, the authors recommend the “5A’s Model” (Ask, Assess, Advise, Agree, Assist) in working with patients. Clinicians should ask for permission before starting a conversation about weight loss and then assess the patient. Assessment should include a complete medical history, including psychosocial, weight, dietary, and other lifestyle history; physical examination; appropriate lab or imaging studies for assessment of root causes of obesity, identification of obesity-related complications and assessment of nutritional status, including risk of malnutrition. Clinicians should advise patients about treatment options and discuss expectations for treatment. Clinicians and patients should agree on goals related to health, dietary patterns and other lifestyle patterns, and weight. Clinicians should assist patients in addressing challenges and barriers to weight management taking into consideration social determinants of health. Because obesity is a chronic disease that requires a long-term approach, the authors suggest that clinicians arrange for follow-up care and refer patients for additional support as needed such as seeing a registered dietician.

As for nutritional recommendations for patients taking anti-obesity medications, the authors suggest the following based on healthy dietary patterns:

  • Energy intake: Energy requirements vary based on an individual’s age, sex, body weight, physical activity level, as well as other factors. Recommended minimum goals for energy intake during weight loss should be personalized. In general, energy intakes of 1,200 to 1,500 kcal/day for women and 1,500 to 1,800 kcal/day for men have been recommended as safe during weight loss.
  • Protein: Greater than 60 to 75 g of protein/day and 0.8 to 1.5 g/kg body weight per day can be recommended. Greater than 1.5 g/kg body weight per day may be considered on an individual basis. Recommended sources of protein include beans, lentils and peas; nuts, seeds and soy products; seafood; lean meat, poultry, low-fat dairy foods and eggs. Meal replacement products typically containing 15–25 g of protein/serving may be recommended when consumption from whole foods is insufficient.
  • Carbohydrates: Between 45% to 65% of energy intake. Limit added sugars to less than 10% of energy intake. Recommended sources include whole grains, fruits, vegetables, nuts and seeds, and dairy foods such as milk and yogurt and dairy alternatives like soy milk.
  • Fats: Between 20% to 35% of energy intake. Limit saturated fat to less than 10% of energy intake. Fried and high-fat foods should be avoided to decrease gastrointestinal side effects associated with anti-obesity medications. Good sources of fats include nuts and seeds, avocado, vegetable oils, fatty fish and seafood.
  • Fiber: Recommended amount is 21–25 g/day for adult women and 30–38 g/day for adult men depending on age. Good sources of fiber include fruits, vegetables and whole grains. Use of a fiber supplement may be considered when patients are unable to meet fiber goals with food alone.
  • Micronutrients: Micronutrients of public health concern for U.S. adults include potassium, calcium and vitamin D. Additional nutrients of concern include iron for women of childbearing age and vitamin B12 in older adults. Individuals with obesity are at increased risk of micronutrient deficiencies such as vitamin D, folate and thiamine. Guidelines recommend increased intake of fruits, vegetables, low-fat dairy products and fortified soy alternatives. Recommendations also include supplementation with a complete multi-vitamin, calcium and vitamin D as appropriate.
  • Fluids: Targeted fluid intake should be greater than 2 to 3 L/day. Recommended sources include water, low-calorie beverages such as unsweetened coffee or tea, or nutrient-dense beverages such as low-fat dairy or soy alternatives. Limitation or avoidance of caffeine is recommended during weight loss due to the potential diuretic effect of high caffeine intake.

The authors recommend ongoing monitoring of dietary intake and nutritional status during treatment with anti-obesity medications. Regular monitoring can facilitate early recognition and management of gastrointestinal symptoms, mood disorders and inadequate nutrient or fluid intake.

The authors explain that limited evidence exists to guide nutritional recommendations for patients receiving new anti-obesity medications that have an efficacy of 15% or more weight reduction. Additional research is needed to address this knowledge gap.

“Simply focusing on weight loss is insufficient for optimal health,” said Jessica Alvarez, PhD, RD, associate professor of medicine, Division of Endocrinology, Metabolism and Lipids, Emory University School of Medicine, Atlanta, Ga. Alvarez was not associated with the research.

She added that “people with obesity are already at risk for some nutrient deficiencies. This is an important guide acknowledging the need for thorough nutritional assessment before and during treatment with anti-obesity medications. Many patients need detailed guidance on what and how much to eat to ensure optimal diet quality, avoid nutrient deficiencies and avoid excessive muscle loss while taking anti-obesity medications. This work also highlights the need for rigorous clinical research to establish dietary recommendations specific to people being treated with anti-obesity medications.”

The current review was based on a PubMed Search using a variety of keywords such as dietary, nutritional, nutrition, weight loss, obesity, obese, very low-calorie diet, malnutrition, bariatric, guidelines and reference. Manuscript reference lists were also reviewed. Because this was a narrative review, searches were augmented with relevant research by expert consensus. Nutritional recommendations were based on evidence from the general population, low-calorie diets, and bariatric surgery, including observations of preoperative patients.