Studies Highlighting The Benefits of Snacking

As food and nutrition professionals, we understand the importance of providing dietary guidance backed by science. We look to the research to inform our recommendations and then translate the science to help our patients and clients make healthier choices.

Below are highlights and links to some of the research on snacking:

WEIGHT MAINTENANCE
Snacking is beneficial for individuals looking to manage their weight since it provides structure to a daily eating plan, even when schedules are erratic. A review paper suggested that individuals who snack throughout the day may have improved weight control over those conforming to a rigid pattern of three meals a day.² Another study suggests that snacking helps appetite control by preventing overeating at meals. The authors noted that eating smaller amounts more frequently may be a more compatible pattern of eating than eating large meals for a physically-active lifestyle.³ One study used NHANES data to determine associations between snacking frequency and overweight/abdominal obesity. The study found inverse relationships between snacking frequency and mean body weight, BMI, the percentile of BMI-for-age, and waist circumference among participating adolescents. In this same study, prevalence for over-weight/obesity and the occurrence of abdominal obesity decreased as snacking frequency and energy consumed from snacks increased.⁴ A fourth study conducted among American adults examined people who skip meals compared to those who do not. The study found that in both categories, the prevalence of overweight/obesity was significantly lower in those who skipped meals but snacked (65.5 + 0.8% vs. 71.6+1.5% ) as well as in non-meal skippers who snacked (62.8 +1.1% vs. 66.7 + 1.2% ), compared to those who did not snack.⁵

WEIGHT MAINTENANCE

Snacking is beneficial for individuals looking to manage their weight since it provides structure to a daily eating plan, even when schedules are erratic. A review paper suggested that individuals who snack throughout the day may have improved weight control over those conforming to a rigid pattern of three meals a day.²

Another study suggests that snacking helps appetite control by preventing overeating at meals. The authors noted that eating smaller amounts more frequently may be a more compatible pattern of eating than eating large meals for a physically-active lifestyle.³ One study used NHANES data to determine associations between snacking frequency and overweight/abdominal obesity. The study found inverse relationships between snacking frequency and mean body weight, BMI, the percentile of BMI-for-age, and waist circumference among participating adolescents. In this same study, prevalence for over-weight/obesity and the occurrence of abdominal obesity decreased as snacking frequency and energy consumed from snacks increased.⁴

A fourth study conducted among American adults examined people who skip meals compared to those who do not. The study found that in both categories, the prevalence of overweight/obesity was significantly lower in those who skipped meals but snacked (65.5 + 0.8% vs. 71.6+1.5% ) as well as in non-meal skippers who snacked (62.8 +1.1% vs. 66.7 + 1.2% ), compared to those who did not snack.⁵

WEIGHT LOSS
Individuals who are looking to lose weight may pre-empt their hunger with planned snacks. One study found that hunger is more intense before meals than before snacks. The satiety ratio was quantified and found to be higher for snacks than meals. It was also observed that afternoon snacks exhibited a high satiety ratio for a modest intake. This suggests that those looking to lose weight can feel fuller on fewer calories by including snacks in their daily meal plan.⁶ Another study provided evidence that restrictions do not have to be put on the snack selection (i.e., type of snack or calories per serving) for snacking to be effective as part of a weight loss plan, as long as total calories are controlled. In the study, adolescent girls were randomly assigned to either a 1,500 kcal/day free-snack program or a 1,500 kcal/day restricted-snack program. Results indicated that both approaches to snacking were equally effective in achieving a modest amount of weight loss.⁷

WEIGHT LOSS

Individuals who are looking to lose weight may pre-empt their hunger with planned snacks. One study found that hunger is more intense before meals than before snacks. The satiety ratio was quantified and found to be higher for snacks than meals. It was also observed that afternoon snacks exhibited a high satiety ratio for a modest intake. This suggests that those looking to lose weight can feel fuller on fewer calories by including snacks in their daily meal plan.⁶

Another study provided evidence that restrictions do not have to be put on the snack selection (i.e., type of snack or calories per serving) for snacking to be effective as part of a weight loss plan, as long as total calories are controlled. In the study, adolescent girls were randomly assigned to either a 1,500 kcal/day free-snack program or a 1,500 kcal/day restricted-snack program. Results indicated that both approaches to snacking were equally effective in achieving a modest amount of weight loss.⁷

SUSTAINING ENERGY
Snacking helps fuel the body to prepare for and recover from exercise and physical activity. Guidelines for glycogen storage stress the value of choosing nutrient-rich high carbohydrate foods along with other foods that provide a good source of protein and other nutrients. These macronutrients may assist in other recovery processes and, in the case of protein, may promote additional glycogen recovery when carbohydrate intake is suboptimal or when frequent snacking is not possible.⁸ Snacking also provides energy during periods of the day when hunger strikes. In one study, those who had eaten a small breakfast spent significantly less time attending to their work than those who had eaten larger meals. Consumption of a mid-morning snack reversed the adverse effect of a small breakfast.⁹

SUSTAINING ENERGY

Snacking helps fuel the body to prepare for and recover from exercise and physical activity. Guidelines for glycogen storage stress the value of choosing nutrient-rich high carbohydrate foods along with other foods that provide a good source of protein and other nutrients. These macronutrients may assist in other recovery processes and, in the case of protein, may promote additional glycogen recovery when carbohydrate intake is suboptimal or when frequent snacking is not possible.⁸

Snacking also provides energy during periods of the day when hunger strikes. In one study, those who had eaten a small breakfast spent significantly less time attending to their work than those who had eaten larger meals. Consumption of a mid-morning snack reversed the adverse effect of a small breakfast.⁹

IMPROVING DIET QUALITY
One role for snacking identified by research is the opportunity to add good-for-you nutrients to the diet. One study among American adolescents showed that foods consumed as snacks provided 12-39% of the day’s total number of portions from the five MyPyramid food groups. Statistically significant nutrients provided by these snacks included Vitamin C and carbohydrates, and snacking was positively related to meeting daily milk and oil recommendations.¹⁰ Additionally, snack foods and increased eating frequency have been found to contribute substantial amounts of whole grains, vitamin E, dietary fiber, iron, folate, calcium, magnesium, potassium, and monounsaturated fatty acids to the diets of Americans.^1,11 A review paper by Gatenby found that snacking contributes significantly to the nutrient quality of the diet. Although those who snacked frequently tended to eat more food in general, the snack foods were not providing “empty calories”; rather, they were providing important vitamins and minerals.¹² An analysis of the food intake records over a two-day period observed that the largest proportion of vitamin C and a large proportion of vitamin A intakes were from snacks, which provided 20% of total daily caloric intake.¹³ Although snacks also contributed to the largest proportions of fat intake in this analysis, the review did not differentiate between types of fat. The revised Dietary Guidelines, released by the United States Department of Agriculture in 2005, emphasize the importance of differentiating between fats. In fact, although the amount of total fat recommended daily intake was increased (up to 35 percent), the guidelines state that most fat should come from unsaturated fats. It is important to note that snacks are a great opportunity to include the “good” mono- and polyunsaturated fats in the diet. In addition, according to the US Department of Agriculture (USDA) Continuing Survey of Food Intakes by Individuals (CSF), ready-to-eat cereals (30.9%), corn and other chips (21.7%), and yeast breads (18.1%) were the major food sources of whole grains.¹⁴ The Healthy Eating Index (HEI) is a “measure of diet quality that assesses conformance to federal dietary guidance.” In comparing the HEI between adolescents who consumed snacks versus adolescents who did not consume snacks, the HEI was higher among those who consumed daily snacks. Therefore, snacking may be positively associated with improved diet quality.¹⁵

IMPROVING DIET QUALITY

One role for snacking identified by research is the opportunity to add good-for-you nutrients to the diet. One study among American adolescents showed that foods consumed as snacks provided 12-39% of the day’s total number of portions from the five MyPyramid food groups. Statistically significant nutrients provided by these snacks included Vitamin C and carbohydrates, and snacking was positively related to meeting daily milk and oil recommendations.¹⁰ Additionally, snack foods and increased eating frequency have been found to contribute substantial amounts of whole grains, vitamin E, dietary fiber, iron, folate, calcium, magnesium, potassium, and monounsaturated fatty acids to the diets of Americans.^1,11

A review paper by Gatenby found that snacking contributes significantly to the nutrient quality of the diet. Although those who snacked frequently tended to eat more food in general, the snack foods were not providing “empty calories”; rather, they were providing important vitamins and minerals.¹² An analysis of the food intake records over a two-day period observed that the largest proportion of vitamin C and a large proportion of vitamin A intakes were from snacks, which provided 20% of total daily caloric intake.¹³

Although snacks also contributed to the largest proportions of fat intake in this analysis, the review did not differentiate between types of fat. The revised Dietary Guidelines, released by the United States Department of Agriculture in 2005, emphasize the importance of differentiating between fats. In fact, although the amount of total fat recommended daily intake was increased (up to 35 percent), the guidelines state that most fat should come from unsaturated fats. It is important to note that snacks are a great opportunity to include the “good” mono- and polyunsaturated fats in the diet. In addition, according to the US Department of Agriculture (USDA) Continuing Survey of Food Intakes by Individuals (CSF), ready-to-eat cereals (30.9%), corn and other chips (21.7%), and yeast breads (18.1%) were the major food sources of whole grains.¹⁴

The Healthy Eating Index (HEI) is a “measure of diet quality that assesses conformance to federal dietary guidance.” In comparing the HEI between adolescents who consumed snacks versus adolescents who did not consume snacks, the HEI was higher among those who consumed daily snacks. Therefore, snacking may be positively associated with improved diet quality.¹⁵

MANAGING DIABETES
Snacks are often major contributors to energy and nutrient intakes among people with diabetes. While meal patterns for people with diabetes differ, most contain at least one snack to help improve glycemic control. The American Diabetes Association states that “snacks can help curb hunger while adding a nutritious energy boost to your day.” Snacking can help Type 1 or 2 diabetes patients better control their blood sugar. In one study, adolescents who lived with their biological parents had glycosylated hemoglobin levels that were approximately 0.5% lower on average than those who lived in alternative family arrangements (i.e. blended and single-parent families). The adolescents who lived with their biological parents also ate more frequent meals and snacks, suggesting a relationship between increased meal and snack frequency and better glycemic control among adolescents with type 1 or 2 diabetes. Regular blood glucose monitoring also mediated this effect.¹⁶ Snacking can also help diabetics decrease the risk for hypoglycemia. A snack two hours after an insulin injection resulted in a less erratic blood glucose profile and reduced the risk of hypoglycemia in patients treated with preprandial regular human insulin.¹⁷

MANAGING DIABETES

Snacks are often major contributors to energy and nutrient intakes among people with diabetes. While meal patterns for people with diabetes differ, most contain at least one snack to help improve glycemic control. The American Diabetes Association states that “snacks can help curb hunger while adding a nutritious energy boost to your day.”
Snacking can help Type 1 or 2 diabetes patients better control their blood sugar. In one study, adolescents who lived with their biological parents had glycosylated hemoglobin levels that were approximately 0.5% lower on average than those who lived in alternative family arrangements (i.e. blended and single-parent families). The adolescents who lived with their biological parents also ate more frequent meals and snacks, suggesting a relationship between increased meal and snack frequency and better glycemic control among adolescents with type 1 or 2 diabetes. Regular blood glucose monitoring also mediated this effect.¹⁶

Snacking can also help diabetics decrease the risk for hypoglycemia. A snack two hours after an insulin injection resulted in a less erratic blood glucose profile and reduced the risk of hypoglycemia in patients treated with preprandial regular human insulin.¹⁷

IMPROVING THE DIET OF OLDER ADULTS
Many older adults experience decreased appetite, taste changes, and depression—these symptoms may lead to decreased food and beverage consumption. This decreased consumption may lead to nutrient deficiencies which may jeopardize their health and quality of life. According to one study, older adults’ micronutrient consumption may only consist of 33%-55% of their Dietary Reference Intakes.¹⁸ Snacking provides an important opportunity to increase the intake of some of these micronutrients. One study found that as snacking frequency increased among older adults, daily intakes of Vitamin A, Vitamin C, Vitamin E, beta-carotene also increased, magnesium, copper, and potassium also increase.¹⁹ Besides providing important micronutrients, snacking also helps older adults to consume enough energy and macronutrients. One study among older adults found that snackers consuming 2 snacks/day on average consumed significantly more energy, carbohydrate, and protein than non-snackers. This increase in macronutrient intake provides important data and support for snacking among older adults.²⁰

IMPROVING THE DIET OF OLDER ADULTS

Many older adults experience decreased appetite, taste changes, and depression—these symptoms may lead to decreased food and beverage consumption. This decreased consumption may lead to nutrient deficiencies which may jeopardize their health and quality of life. According to one study, older adults’ micronutrient consumption may only consist of 33%-55% of their Dietary Reference Intakes.¹⁸ Snacking provides an important opportunity to increase the intake of some of these micronutrients. One study found that as snacking frequency increased among older adults, daily intakes of Vitamin A, Vitamin C, Vitamin E, beta-carotene also increased, magnesium, copper, and potassium also increase.¹⁹

Besides providing important micronutrients, snacking also helps older adults to consume enough energy and macronutrients. One study among older adults found that snackers consuming 2 snacks/day on average consumed significantly more energy, carbohydrate, and protein than non-snackers. This increase in macronutrient intake provides important data and support for snacking among older adults.²⁰

CHILDREN AND ADOLESCENTS: RAISING HEALTHY EATERS
The American Academy of Pediatrics recommends that children and adolescents eat three scheduled meals and 1-2 snacks daily. Following these guidelines helps to promote structured eating habits, encourage healthy lifestyles, and decrease likelihood of obesity. Another study conducted among adolescents sought to determine the impact snacking had on nutrient intake and the likelihood of meeting nutrient recommendations outlined in the U.S. Department of Agriculture’s MyPyramid Food Guidance System. This study found that as snacking increased, so did the consumption of Vitamin C and carbohydrates, and snacking was also positively related to meeting daily milk and oil recommendations.¹⁰ A third study found that adolescents who ate two or more snacks/day were less likely to be overweight/obese and to carry abdominal adiposity when compared to non-snackers. Risks for overweight/obesity were also inversely related to snacking.²¹

CHILDREN AND ADOLESCENTS: RAISING HEALTHY EATERS

The American Academy of Pediatrics recommends that children and adolescents eat three scheduled meals and 1-2 snacks daily. Following these guidelines helps to promote structured eating habits, encourage healthy lifestyles, and decrease likelihood of obesity.
Another study conducted among adolescents sought to determine the impact snacking had on nutrient intake and the likelihood of meeting nutrient recommendations outlined in the U.S. Department of Agriculture’s MyPyramid Food Guidance System. This study found that as snacking increased, so did the consumption of Vitamin C and carbohydrates, and snacking was also positively related to meeting daily milk and oil recommendations.¹⁰

A third study found that adolescents who ate two or more snacks/day were less likely to be overweight/obese and to carry abdominal adiposity when compared to non-snackers. Risks for overweight/obesity were also inversely related to snacking.²¹

MEETING NUTRIENT NEEDS DURING PREGNANCY
In 1992, the Institute of Medicine (IOM) released dietary and weight gain recommendations for pregnant women. One of the IOM’s recommendations to pregnant women was to eat three meals and two snacks daily to help meet the increased nutrient needs during pregnancy. Snacking during pregnancy may also improve the baby’s health: one study found that pregnant women who consumed three meals a day but without snacks had the highest rate of preterm birth (16.6% prevalence), compared to the rate of preterm birth among women who met the IOM’s recommendations to eat three meals and two snacks daily during pregnancy (4% prevalence).²²

MEETING NUTRIENT NEEDS DURING PREGNANCY

In 1992, the Institute of Medicine (IOM) released dietary and weight gain recommendations for pregnant women. One of the IOM’s recommendations to pregnant women was to eat three meals and two snacks daily to help meet the increased nutrient needs during pregnancy.

Snacking during pregnancy may also improve the baby’s health: one study found that pregnant women who consumed three meals a day but without snacks had the highest rate of preterm birth (16.6% prevalence), compared to the rate of preterm birth among women who met the IOM’s recommendations to eat three meals and two snacks daily during pregnancy (4% prevalence).²²

GENERAL CONCLUSIONS TO BE DRAWN FROM SNACKING RESEARCH
Evidence suggests that snacking is inversely related to body weight and may promote a healthier diet. Snacks may benefit special populations including people with diabetes, children and adolescents, older adults, and pregnant women. Currently, there is no consensus on a definition for snacking. In order for us to have a better understanding of the roles snacking plays in health, it is important to conduct more research regarding snacking under the terms of one universal definition. The absence of an established definition of snacking has left several gaps in our understanding of snacking including meaningful trend data, snacking’s impact on general health, the impact of snacking on weight and energy intake, and recommendations for snacking.¹ Although more research is needed regarding snacking and its role in healthy lifestyles, it is important to note the difference between mindful eating and mindless eating.

GENERAL CONCLUSIONS TO BE DRAWN FROM SNACKING RESEARCH

Evidence suggests that snacking is inversely related to body weight and may promote a healthier diet.
Snacks may benefit special populations including people with diabetes, children and adolescents, older adults, and pregnant women.
Currently, there is no consensus on a definition for snacking. In order for us to have a better understanding of the roles snacking plays in health, it is important to conduct more research regarding snacking under the terms of one universal definition.
The absence of an established definition of snacking has left several gaps in our understanding of snacking including meaningful trend data, snacking’s impact on general health, the impact of snacking on weight and energy intake, and recommendations for snacking.¹
Although more research is needed regarding snacking and its role in healthy lifestyles, it is important to note the difference between mindful eating and mindless eating.

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Studies Highlighting The Benefits of Snacking