New findings from the Monell Center reveal that weight gain of formula-fed infants is influenced by the type of formula the infant is consuming. The findings have implications related to the infant’s risk for the development of obesity, diabetes and other diseases later in life. “Events early in life have long-term consequences on health and one of the most significant influences is early growth rate,” said study lead author Julie Mennella, Ph.D., a developmental psychobiologist at Monell. “We already know that formula-fed babies gain more weight than breast-fed babies. But we didn’t know whether this was true for all types of formula.”
While most infant formulas are cow’s milk-based, other choices include soy-based and protein hydrolysate-based formulas. Protein hydrolysate formulas contain pre-digested proteins and typically are fed to infants who cannot tolerate the intact proteins in other formulas. In adults, pre-digested proteins are believed to act in the intestine to initiate the end of a meal, thus leading to smaller meals and intake of fewer calories. Based on this, the authors hypothesized that infants who were feeding protein hydrolysate formulas would eat less and have an altered growth pattern relative to infants feeding cow’s milk-based formula.
In the study, published online in the journal Pediatrics, infants whose parents had already decided to bottle-feed were randomly assigned at two weeks of age to feed either a cow’s milk-based formula (35 infants) or a protein hydrolysate formula (24 infants) for seven months. Both formulas contained the same amount of calories, but the hydrolysate formula had more protein, including greater amounts of small peptides and free amino acids. Infants were weighed once each month in the laboratory, where they also were videotaped consuming a meal of the assigned formula. The meal continued until the infant signaled that s/he was full.
Over the seven months of the study, the protein hydrolysate infants gained weight at a slower rate than infants fed cow milk formula. Linear growth, or length, did not differ between the two groups, demonstrating that the differences in growth were specifically attributable to weight. “All formulas are not alike,” said Mennella. “These two formulas have the same amount of calories, but differ considerably in terms of how they influence infant growth.”
When the data were compared to national norms for breast-fed infants, the rate of weight gain of protein hydrolysate infants was comparable to the breast milk standards; in contrast, infants fed cow’s milk formula gained weight at a greater rate than the same breast milk standards. Analysis of the laboratory meal revealed the infants fed the protein hydrolysate formula consumed less formula during the meal. “One of the reasons the protein hydrolysate infants had similar growth patterns to breast-fed infants, who are the gold standard, is that they consumed less formula during a feed as compared to infants fed cow’s milk formula” said Mennella. “The next question to ask is: Why do infants on cow’s milk formula overfeed?”
The findings highlight the need to understand the long-term influences of infant formula composition on feeding behavior, growth, and metabolic health. Future studies will utilize measures of energy metabolism and expenditure to examine how the individual formulas influence growth, and how each differs from breastfeeding. Also contributing to the study, which was funded by the National Institute of Child Health and Human Development, were Monell scientists Gary Beauchamp and Alison Ventura.
The pilot study used four women, all of whom were breast cancer survivors, and monitored changes in their blood of key molecules involved in the growth of cancer cells. The participants were asked to fast on the day of the tests and had blood samples taken before and after eating a portion of watercress. The scientists found that six hours after they had eaten the leaves, the women experienced a drop in the activity of a molecule called 4E binding protein, which is thought to be involved in helping cancer cells survive.
Laboratory studies also showed that extracts taken from watercress leaves inhibited the growth of breast cancer cells. The findings build on epidemiological studies that have shown people who eat watercress and other vegetables rich in isothiocyanates, such as broccoli and cabbage, are at lower risk of developing cancer.
Hazel Nunn, Cancer Research UK's health information manager, said the current study was too small to draw any firm conclusions.
She added: “Watercress may well have benefits but there's no reason to believe that it should be superior to a generally healthy, balanced diet that is high in fibre, vegetables and fruit and low in red and processed meat, salt, saturated fat and alcohol.”
Due to the many different ways that previous studies have investigated the association between height and heart disease, Dr Paajanen and her colleagues decided to compare the shortest group to the tallest group instead of using a fixed height limit.
From the total of 1,900 papers, the researchers selected 52 that fulfilled all their criteria for inclusion in their study. These included a total of 3,012,747 patients. On average short people were below 160.5 cms high and tall people were over 173.9 cms. When men and women were considered separately, on average short men were below 165.4 cms and short women below 153 cms, while tall men were over 177.5 cms and tall women over 166.4 cms.
Dr Paajanen and her colleagues found that compared to those in the tallest group, the people in the shortest group were nearly 1.5 times more likely to die from cardiovascular disease (CVD) or coronary heart disease (CHD), or to live with the symptoms of CVD or CHD, or to suffer a heart attack, compared with the tallest people.
Looking at men and women separately, short men were 37% more likely to die from any cause compared with tall men, and short women were 55% more likely to die from any cause compared with their taller counterparts.
“Due to the heterogeneity of studies, we cannot reliably answer the question on the critical absolute height,” write the authors in their study. “The height cut-off points did not only differ between the articles but also between men and women and between ethnic groups. This is why we used the shortest-vs.-tallest group setting.”
The findings have clinical implications. Dr Paajanen said: “The results of this systematic review and meta-analysis suggest that height may be considered as a possible independent factor to be used in calculating people's risk of heart disease. Height is used to calculate body mass index, which is a widely used to quantify risk of coronary heart disease.”
It is not known why short stature should be associated with increased risk of heart disease. Dr Paajanen said: “The reasons remain open to hypotheses. We hypothesize that shorter people have smaller coronary arteries and smaller coronary arteries may be occluded earlier in life due to factors that increase risk, such as a poorer socioeconomic background with poor nutrition and infections that result in poor foetal or early life growth. Smaller coronary arteries also might be more affected by changes and disturbances in blood flow. However, recent findings on the genetic background of body height suggest that inherited factors, rather than speculative early-life poor nutrition or birth weight, may explain the association between small stature and an increased risk of heart disease in later life. We are carrying out further research to investigate these hypotheses.”
Dr Paajanen said that it was important that short people should not be worried by her findings. “Height is only one factor that may contribute to heart disease risk, and whereas people have no control over their height, they can control their weight, lifestyle habits such as smoking, drinking and exercise and all of these together affect their heart disease risk. In addition, because the average height of populations is constantly increasing, this may have beneficial effect of deaths and illness from cardiovascular disease.”
In an editorial on the research published at the same time , Jaakko Tuomilehto, Professor of Public Health at the University of Helsinki, Helsinki, Finland, welcomed the study, writing: “The systematic review and meta-analysis on this topic . . . is well justified 60 years after the first observation and the hundreds of other papers which have been published since then on this topic. The results are unequivocal: short stature is associated with increased risk of coronary heart disease. This meta-analysis provides solid proof for this, but, as the authors conclude 'The possible pathophysiological, environmental, and genetic background of this peculiar association is not known'.”
He suspects that environmental events affecting growth before and after birth may be involved. “Socio-economic adversity in childhood is . . . associated with delayed early growth and shorter adult stature. The so-called catch-up growth during the first years of life among children who are born small has negative health effects in adulthood; much of the early growth is due to greater fat accumulation. Thus, it is most likely that short stature is the link to coronary heart disease, and that tallness is not a primary factor in preventing the disease, although it indicates healthy growth. Short stature seems to be a marker for risk.”
While more work is needed to understand the exact nature of the mechanisms at work, he writes that information on height can be used now for the prevention of heart disease and other chronic diseases linked to shortness. “Full term babies who are born small are likely to be short as adults. They should receive preventive attention early on. The primordial prevention of chronic diseases should start during foetal life, and health promotion should be targeted to all pregnant women with the aim of health development of the foetus. Low birth weight and some other birth characteristics can reveal potential problems during this period of life. After that, in babies with low birth weight, it is important to avoid excessive catch-up growth, i.e. early-life fatness.”
In adult life it becomes more difficult to discover best practices, but Prof Tuomilehto, thinks it is likely short adults would benefit from more aggressive risk factor reduction.
He concludes: “Most of us know approximately our own height ranking, and, if we are at the low end, we should take coronary risk factor control more seriously. On the other hand, tall people are not protected against coronary heart disease, and they also need to pay attention to the same risk factors as shorter people.”
Dietitians and other health professionals have long recognized the importance of establishing healthful nutrition practices during teenage years. Diet and exercise patterns adopted during these prime developmental years set the stage for life-long habits that can mean the difference between vitality and infirmity in later years.
Your calorie needs vary depending on your growth rate, degree of physical maturation, body composition, and activity level. However, you do need extra nutrients to support the adolescent growth spurt, which, for girls, begins at ages 10 or 11, reaches its peak at age 12, and is completed by about age 15. In boys, it begins at 12 or 13 years of age, peaks at age 14, and ends by about age 19.
In addition to other nutrients, adequate amounts of iron and calcium are particularly important as your body undergoes this intensive growth period. From ages nine to 18 years, both males and females are encouraged to consume a calcium-rich diet (1,300 milligrams daily) in order to ensure adequate calcium deposits in the bones. This may help reduce the incidence of osteoporosis in later years. The recommended calcium intake can be achieved by getting at least three cups of fat-free or low-fat milk daily or the equivalent amount of low-fat yogurt and/or low-fat cheese. For those who don’t wish to consume dairy products, a variety of other calcium sources are available such as green, leafy vegetables, calcium-fortified soy products, and other calcium-fortified foods and beverages.
To meet energy needs, teenagers should eat at least three meals a day, beginning with breakfast. Studies show eating breakfast affects both cognitive and physical performance; that is, if you eat breakfast, you may be more alert in school and better able to learn and to perform sports or other physical activities.
Snacks also form an integral part of meal patterns for teenagers. You often cannot eat large quantities of food at one sitting and often feel hungry before the next regular mealtime.Healthy mid-morning and midafternoon snacks may be appropriate for you you.
Fast-growing, active teenagers may have tremendous energy needs. Although your regular meals can be substantial, you may need snacks to supply energy between meals and to meet your daily nutrient needs. If you are less active or who have already gone through the growth spurt, you may need to cut out the snacking.
Teenager’s food choices are often influenced by social pressure to achieve cultural ideals of thinness, gain peer acceptance, or assert independence from parental authority. These factors may increase your risk for developing eating disorders. An eating disorder is an emotional and physical problem that is associated with an obsession with food, body weight, or body shape. A teenager with an eating disorder diets, exercises, and/or eats excessively as a way of coping with the physical and emotional changes of adolescence. The three most common types of eating disorders are anorexia, bulimia, and binge eating. Each type has its own symptoms and diagnosis.
According to the National Mental Health Information Center, as many as 10 million girls and women and one million boys and men are struggling with eating disorders such as anorexia nervosa (a disorder causing people to severely limit their food intake) or bulimia (a disorder in which people binge and purge by vomiting or using laxatives). Both anorexia and bulimia can lead to convulsions, kidney failure, irregular heartbeats, osteoporosis, and dental erosion. Those suffering from compulsive overeating or binge-eating disorder are at risk for heart attack, developing high blood pressure and high cholesterol, kidney disease and/or failure, arthritis, bone deterioration, and stroke.
Seeing a dietitian like Nastaran for medical nutrition therapy as well as seeing a medical specialist for psychotherapy are two integral components in the treatment of eating disorders. These are such complex illnesses that the expertise of multidisciplinary healthcare professionals is required.
Overweight and Obesity
Adults are not alone in the concern about weight management. In addition to the increase in the prevalence of adults who are obese or overweight, adolescent and childhood obesity and overweight are also on the rise.
Data from the US National Health and Nutrition Examination Survey (NHANES 2003-2004), indicate that 14 percent of two to five year olds and 17 percent of children and adolescents ages 12-19 years in the United States are overweight. The prevalence of overweight children and adolescents has quadrupled and tripled, respectively, in the last 30 years. Only a small percentage of overweight children may attribute their problem to endocrine disorder or other underlying physical problems. Overweight and obesity can be determined by Body Mass Index (BMI).
If you are overweight, you need to reduce the rate of weight gain while still allowing for growth and development. Overweight children and adolescents are more likely to be overweight or obese as adults. Therefore, health professionals emphasize healthful eating and the importance of physical activity as a life-long approach to weight management and to overall good health and quality of life. Before going on a diet, a healthcare provider and/or dietitian like Nastaran should always be consulted.
Strong bones, good muscle tone, and lower risk of developing chronic diseases are some of the key benefits derived from regular physical activity. Furthermore, being physically active promotes psychological well-being and reduces feelings of depression and anxiety. According to the Centers for Disease Control and Prevention/Division of Adolescent and School Health, 77 percent of children aged nine to 13 years participate in free-time physical activity and only 39 percent engage in organized physical activity. Among high school students, 63 percent participate in vigorous physical activity and just 25 percent engage in sufficient moderate physical activity. Twelve percent engage in little or no physical activity at all.
Participation in physical activity tends to decline as you get older. The long-term consequences of physical inactivity include an increased risk of type 2 diabetes, high blood pressure, high blood cholesterol, asthma, arthritis, and premature death. To maintain good health status you should engage in at least 60 minutes of physical activity on most, preferably all, days of the week
Source: International Food Information Council