Alcohol Intake and Weight Loss during an Intensive Lifestyle Intervention for Adults with Overweight/Obesity and Diabetes

Ariana M Chao; Thomas A Wadden; Jena Shaw Tronieri; Robert I Berkowitz

doi:10.1002/oby.22316

. Author manuscript; available in PMC: 2019 May 13.

Published in final edited form as: Obesity (Silver Spring). 2018 Nov 13;27(1):30–40. doi: 10.1002/oby.22316

Alcohol Intake and Weight Loss during an Intensive Lifestyle Intervention for Adults with Overweight/Obesity and Diabetes

Ariana M Chao ^1,², Thomas A Wadden ², Jena Shaw Tronieri ², Robert I Berkowitz ^2,³

PMCID: PMC6309276 NIHMSID: NIHMS1504978 PMID: 30421851

Abstract

Objective:

To assess whether alcohol consumption decreases during an intensive lifestyle intervention (ILI) and whether alcohol consumption is associated with weight loss among participants with overweight/obesity and type 2 diabetes.

Methods:

Participants (n=4,901) were from the Action for Health in Diabetes (Look AHEAD) study, an RCT that compared an ILI to a diabetes support and education (DSE) control. Mixed effects models were used to estimate the effect of the ILI on alcohol consumption, and the influence of alcohol consumption on weight loss at year 4.

Results:

ILI and DSE participants did not differ in changes in alcohol consumption. Alcohol intake was not associated with weight loss at year 1 of the ILI. ILI participants who abstained from alcohol lost 5.1±0.3% of initial weight at year 4, compared to a significantly (p=0.04) smaller 2.4±1.3% for consistent-heavy drinkers. ILI participants who abstained from alcohol consumption over the 4 years lost 1.6±0.5% more weight relative to individuals who drank alcohol at any time during the intervention (p=0.003). DSE participants did not differ in weight loss by alcohol consumption.

Conclusions:

Heavy alcohol drinkers are at risk for suboptimal long-term weight loss. Decreasing alcohol consumption may improve weight management among individuals with diabetes.

Keywords: Alcohol, obesity, weight loss, type 2 diabetes, treatment

Introduction

Alcoholic beverages are a top contributors of calories in Americans’ diets.¹ The percent of people who consume alcohol has increased since the early 2000s.^2,3 Over 70% of Americans report consuming alcohol at least once a year.^2,3 The per capita intake from alcoholic beverages is 109 kcals/day.⁴ A meta-analysis of prospective observational studies demonstrated that relative to individuals who drank minimal alcohol, light-to-moderate alcohol consumption was associated with a lower risk of type 2 diabetes.⁵

However, alcohol is energy dense, containing 7.1 kcals/gram and may be an important factor related to weight. Alcohol is inefficient in facilitating satiety, and calories from alcohol usually add, rather than substitute, for energy ingested through other dietary sources.^6,7 Consumption of alcohol is linked to disinhibited eating⁸ and increased food intake,^9,10 possibly through neural mechanisms related to energy regulation.^8,11 Some studies have supported a relationship between increased alcohol consumption and higher body weight,^12–16 while others have suggested an inverse relation¹⁷ or no association.^7,18–20 Possible reasons for these discrepancies include the use of self-reported height and weight, variable (and often short) follow-up, and inconsistent control for confounders such as smoking status.

Though the association between alcohol consumption and body weight is unclear, decreasing or eliminating calories from alcohol is typically recommended during weight loss. Despite the potential benefits of reducing alcohol consumption on weight management, few studies have examined whether participants report changes in alcohol intake during weight loss treatment^21–23 and whether alcohol influences weight loss. One study demonstrated no change in alcohol intake during a lifestyle intervention²³ while another showed decreased intake at the end of treatment.²² Alcohol intake was not related to weight change, but was associated with change in end-of-treatment energy intake.²² Research is needed to assess changes in alcohol consumption during weight loss, and the effect of alcohol on weight management.

The present study used data from the Action for Health in Diabetes (Look AHEAD) study to address these questions. Look AHEAD is a 16-center randomized clinical trial that compared the effects of an intensive lifestyle intervention (ILI) to a diabetes support and education (DSE) control group on the incidence of major cardiovascular events.²⁴ The aims of this study were to: 1) assess the effect of the ILI on alcohol consumption over 4 years; and 2) examine whether 4-year weight loss outcomes were related to alcohol consumption over this time. We hypothesized that the ILI, as compared to the DSE, would have greater declines in alcohol consumption from baseline to year 4. We also hypothesized that in the ILI, individuals who reported greater alcohol consumption would lose less weight than those with lower alcohol consumption over the 4 years.

Methods

Participants

As reported previously, 5,145 participants were recruited from across the U.S.²⁵ Individuals had type 2 diabetes, were 45–76 years of age, and had a body mass index (BMI) ≥25 kg/m² (or ≥27 kg/m² if on insulin). The current study used the Look AHEAD public access data set, a subset of 4,901 participants from the cohort; participants from the Native American sites were not included due to consent limitations.

Interventions

Details about the study interventions have been published previously.²⁶ In brief, participants were randomly assigned to ILI or DSE.^26,27 The ILI consisted of individual and group sessions focused on improving diet and physical activity. Participants were prescribed a calorie goal of 1200–1800 kcal/day (based on weight) and a physical activity goal of ≥175 minutes/week of moderate-intensity activity. The ILI group was told about the number of calories in alcohol, advised to decrease their alcohol consumption as a means of reducing caloric intake, and told that dietary guidelines recommended no more than two drinks per day for men and no more than one drink per day for women. Participants in DSE were invited to three group sessions each year focused on diet, physical activity, or social support.

Assessments

Assessments were completed by certified staff members masked to intervention assignment.

Demographic and clinical characteristics.

Self-report forms were used to collect demographic and health data. Weight and height were measured in duplicate following standardized procedures.²⁵ Glycated hemoglobin level was measured annually.

Alcohol.

Alcohol consumption was assessed yearly using a self-report questionnaire that asked similar questions as those recommended by the National Institute on Alcohol Abuse and Alcoholism’s (NIAAA).²⁸ Participants were asked “Did you drink any alcoholic beverages in the past year?” and follow-up questions to assess the number of drinks of wine, beer, and liquor typically consumed each week. One drink was considered a 5-ounce glass of wine, 12-ounce glass, can or bottle of beer, or 1.5 ounces of liquor. Responses were totaled to generate a score for number of drinks per week.

Dietary intake.

Dietary intake was measured on 50% of participants at each clinical site using a self-administered 134-line item food frequency questionnaire that assessed typical consumption during the past 6 months. Calories from alcohol were computed based on daily grams of alcohol consumed per day multiplied by 7.1 kcals/gram.

Physical activity.

Physical activity was assessed using the Paffenbarger Activity Questionnaire (PAQ),²⁹ which provides an estimate of weekly energy expenditure from moderate intensity physical activity. Participants at eight centers completed the questionnaire at baseline, and years 1 and 4.

Depressive symptoms and quality of life.

The Beck Depression Inventory (BDI-1A) was used to assess depressive symptoms over the previous 2 weeks.³⁰ The 36-item Short-Form Health Survey was used to assess physical and mental health-related quality of life.³¹

Definition of Alcohol Groups

Baseline.

NIAAA’s drinking categories guided classification of baseline alcohol intake, based on the average quantity of alcohol consumed per week.³² Categories were: 1) non-drinkers (no drinking at baseline); 2) light drinking (<7 drinks/week for men and <4 drinks/week for women); 3) moderate drinking (7–14 drinks/week for men and 4–7 drinks/week for women); and 4) heavy drinking (>14 drinks/week for men and >7 drinks/week for women).

Year 1.

To describe longitudinal drinking patterns at 1 year, we created categories based on the baseline and year-1 reports of drinking in the past year (yes/no) and the average quantity of alcohol consumed per week. The groups were: 1) those who were abstinent at both times; 2) participants who drank at baseline only; 3) those who endorsed drinking at year 1 only; 4) individuals who drank at both baseline and year 1 averaging to a light amount (<7 drinks/week for men and <4 drinks/week for women); 5) those who drank at both times averaging to a moderate amount (7–14 drinks/week for men and 4–7 drinks/week for women); and 6) participants who drank at both times averaging to a heavy amount (>14 drinks/week for men and >7 drinks/week for women).

Year 4.

At year 4, groups were formed in a similar manner as in year 1. The groups were: 1) those who were abstinent at every survey (abstainers); 2) those who reported drinking at some years between baseline to 4 years (inconsistent drinkers); 3) those who drank at every year they were surveyed, averaging to a light amount (consistent-light); 4) those who reported drinking at every year surveyed, averaging to a moderate amount (consistent-moderate); and 5) those who drank at every year surveyed, averaging to a heavy amount (consistent-heavy). To be included, participants had to complete the alcohol survey at three or more timepoints.

Statistical Analyses

Baseline characteristics were compared by baseline alcohol group using ANOVAs and chi-squared tests. We estimated the effect of the ILI (vs DSE) on total alcohol consumption using linear mixed models, with the change from baseline to year 4 in drinks consumed per week as the main outcome. Models were estimated including all participants and repeated including only participants who endorsed drinking alcohol at baseline. We conducted post-hoc analyses examining changes from baseline to year 1, changes in wine, beer, and liquor consumption, and changes based on baseline alcohol consumption and year-4 alcohol consumption groups. We tested an interaction term for gender and change in alcohol consumption and repeated analyses stratified by gender.

The co-primary outcome compared 4-year percentage change in baseline weight based on the trajectory of alcohol consumption across 4 years. Models were analyzed stratified by treatment using a piecewise, linear mixed-effects model with a breakpoint at year 1. Models were adjusted for baseline demographic and clinical differences among alcohol consumption groups. Similar analyses were conducted to examine changes during the first year, when the intervention was most intensive and weight losses were the largest, using the year-1 alcohol groups.

Participants were compared based on alcohol trajectory and categorical weight losses at year 4 (e.g., ≥10% loss) using chi-squared tests. Exploratory analyses were conducted to estimate changes in self-reported dietary intake and physical activity based on 4-year alcohol trajectory. Analyses were performed using SPSS v.25 with a type I error rate of 0.05.

Results

Baseline Differences Based on Baseline Alcohol Consumption

At baseline, 38.1% of the cohort reported not drinking alcohol in the past year, 53.8% reported light drinking, 6.3% reported moderate drinking, and 1.7% reported heavy drinking. Characteristics of participants by baseline alcohol consumption are presented in Table 1.

Table 1.

Demographic and clinical characteristics by baseline alcohol use

		None	Light	Moderate	Heavy	P-value

Participants		1867 (38.1)	2637 (53.8)	309 (6.3)	82 (1.7)
Total/week		0^a	1.09 (1.6)^b	8.1 (3.0)^c	16.2 (8.8)^d	<0.001
Beers/week		0^a	0.3 (0.9)^b	2.7 (3.5)^c	4.6 (9.3)^d	<0.001
Wine/week		0^a	0.5 (0.9)^b	3.3 (3.4)^c	6.7 (5.7)^d	<0.001
Liquor/week		0^a	0.2 (0.7)^b	2.1 (3.0)^c	4.9 (5.4)^d	<0.001
Age, y		59.3 (6.8)^a	58.6 (6.7)^b,c	59.6 (6.9)^a,b	60.5 (7.4)^a,b	<0.001
Sex
	Male	571 (30.6)^a	1221 (46.3)^b	198 (64.1 )^c	39 (47.6)^b	<0.001
	Female	1296 (69.4)^a	1416 (53.7)^b	111 (35.9)^c	43 (52.4)^b
Race/ethnicity
	White	1067 (57.2)^a	1887 (71.6)^b	229 (74.1)^b	61 (74.4)^b	<0.001
	Hispanic	368 (19.7)^a	273 (10.4)^b	30 (9.7)^b	5 (6.1)^b
	African American/Black	364 (19.5)^a	385 (14.6)^b	39 (12.6)^b	13 (15.9)^a,b
	Other/Mixed	68 (3.6)^a	92 (3.5)^a	11 (3.6)^a	3 (3.7)^a
Education
	<13 y	512 (27.4)^a	358 (13.6)^b	40 (12.9)^b	14 (17.1 )^b	<0.001
	13–16 y	728 (39.0)^a	967 (36.7)^a	78 (25.2)^b	25 (30.5)^a,b
	>16 y	588 (31.5)^a	1256 (47.6)^b	185 (59.9)^c	41 (50.0)^b,c
Married		1201 (64.4)	1747 (66.2)	222 (71.8)	54 (65.9)	0.07
Smoking status
	Never	1067 (57.2)^a	1231 (46.7)^b	100 (32.4)^c	25 (30.5)^c	<0.001
	Past	730 (39.1)^a	1288 (48.8)^b	189 (61.2)^c	48 (58.5)^b,c
	Present	68 (3.6)^a	112 (4.2)^a’b	20 (6.5)^b’c	8 (9.8)^c
Body mass index		36.1 (5.9)^a	36.1 (5.9)^a	34.8 (5.7)^b	33.2 (4.0)^b	<0.001
Glycated hemoglobin level, %		7.3 (1.1)^a	7.3 (1.2)^a	7.0 (1.0)^b	7.3 (1.2)^a,b	<0.001
Daily caloric intake, kcal¹		1907.3	2017.4	2119.2	2396.9	<0.001
		(933.8)^a	(825.1)^b	(842.1)^b,c	(1040.4)^c
Daily caloric intake from alcohol^1,2		0 (0)^a	12.7 (25.0)^b	74.8 (70.2)^c	142.7 (136.4)^d	<0.001
Daily fat intake, %^a		39.8 (7.2)	40.2 (6.8)	39.5 (7.0)	39.0 (6.9)	0.34
Daily protein intake, %^a		17.3 (3.0)^a	17.2 (2.8)^a	16.8 (2.6)^a,b	15.7 (3.0)^b	0.001
Daily intake carbohydrates, %^a		44.5 (7.9)^a	43.4 (7.4)^b	41.8 (7.2)^b	41.0 (9.2)^b	<0.001
Insulin use, yes		341 (18.9)^a	359 (14.1)^b,c	30 (10.1)^c	16 (21.3)^a,b	<0.001
Physical activity (kcals/week)³		786.0	850.7	1298.6	923.7	<0.001
		(1188.0)^a	(1021.6)^a	(1645.1)^b	(1127.4)^a,b
Duration of diabetes, y		7.2 (6.7)^a	6.5 (6.3)^b	5.8 (5.3)^b	6.7 (6.8)^a,b	<0.001
History of cardiovascular disease		263 (14.1)	367 (13.9)	51 (16.5)	7 (8.5)	0.30
Depressive symptoms		5.4 (5.0)^a	5.4 (4.8)^a	4.6 (4.3)^b	5.6 (4.8)^a,b	0.02
SF-36, Physical component score		47.3 (8.2)^a	48.3 (7.7)^b	49.7 (7.3)^c	47.7 (8.5)^a,b,c	<0.001
SF-36, Mental component score		54.5 (8.1)^a	53.9 (8.0)^a	54.9 (6.5)^a	53.9 (8.2)^a	0.02

Open in a new tab

Mean (SD) or n(%).Value with different superscript letters across columns are significantly different from one another at p<0.05. These post-hoc comparisons were only performed when the group comparison p-value was <0.05.

Completed by 50% of participants (n=2612). Includes calories from alcohol.

Calculated using grams of alcohol multiplied by 7.1 kcals/gram.

Completed by participants at 8 clinical centers (n= 2395).

Alcohol Consumption by Treatment Group

At year 4, weight data were obtained on 90.1% of the sample, and both weight and alcohol data were available for 88.6% of participants. Individuals who were moderate drinkers at baseline were more likely to complete the full 4-year assessment (weight and questionnaire data) than were those in the other alcohol categories (92.9% vs 87.5% for never drinkers, 88.8% for light drinkers, 90.2% for heavy drinkers; p=0.04).

The ILI and DSE groups did not differ by baseline alcohol consumption categorization (p=0.61). ILI and DSE participants did not differ significantly in changes from baseline to year 1 or from baseline to year 4 in total alcohol consumption or wine, beer, and liquor consumed (ps>0.05; Table 2). ILI and DSE groups did not differ in alcohol consumption (ps>0.05) when restricted to participants who drank alcohol at baseline or when stratified by baseline alcohol group (ps>0.05; Table S1) or by year-4 alcohol consumption group (ps>0.05; Table S1). Gender did not significantly interact with treatment group and change in consumption of total alcohol (p=0.60), wine (p=0.27; Table S2), beer (p=0.45), or liquor (p=0.54) at year 4. Statistical conclusions were the same at year 1.

Table 2.

Mean of baseline values and changes in weekly alcohol consumption from baseline to year 1 and baseline to year 4 for participants who were assigned to intensive lifestyle intervention program (ILI; n=2,448) or diabetes support and education (DSE; n=2,453)

	All Participants			Participants who Drank Alcohol at Baseline

Variable	ILI (n = 2,448)	DSE (n = 2,453)	p-value	ILI (n = 1,531)	DSE (n = 1,500)	p-value
Total alcohol
Baseline	1.3±0.04	1.4±0.04	0.37	2.1±0.1	2.2±0.1	0.13
Change to year 1	−0.1±0.1	+0.03±0.1	0.35	−0.2±0.1	−0.01±0.14	0.33
Change to year 4	+0.2±0.1	+0.1±0.1	0.59	+0.2±0.2	+0.1±0.2	0.60
Wine
Baseline	1.0±0.03	1.0±0.04	0.28	1.0±0.04	1.1±0.04	0.29
Change to year 1	+0.2±0.1	+0.2±0.1	0.84	+0.2±0.1	+0.2±0.1	0.93
Change to year 4	+0.3±0.1	+0.1±0.1	0.25	+0.4±0.1	+0.2±0.1	0.20
Beer
Baseline	0.7±0.03	0.7±0.03	0.81	0.7±0.03	0.7±0.03	0.86
Change to year 1	−0.1±0.1	+0.01±0.1	0.16	−0.1±0.1	+0.1±0.1	0.18
Change to year 4	−0.01±0.1	−0.1±0.1	0.65	+0.1±0.1	−0.01±0.1	0.62
Liquor
Baseline	0.6±0.03	0.6±0.03	0.26	0.6±0.03	0.6±0.03	0.25
Change to year 1	+0.03±0.1	+0.1±0.1	0.54	+0.1±0.1	+0.1±0.1	0.54
Change to year 4	+0.1±0.1	+0.02±0.1	0.56	+0.2±0.1	+0.1±0.1	0.60

Open in a new tab

Note. Values shown are the mean ± SE for number of drinks per week.

Groups at year 1.

In the ILI and DSE groups, a similar percentage of participants were classified as abstinent from alcohol at baseline and year 1 (39.5% vs 40.5%, respectively); baseline only (12.0% vs 11.0%); and year 1 only (5.1% vs 4.3%). The groups did not differ significantly (p=0.67) in the percent of people who drank at both times who were classified as light drinkers (34.6% vs 34.5%); moderate drinkers (6.8% vs 7.4%); and heavy drinkers (2.0% vs 2.3%).

Groups at year 4.

From baseline to 4 years, ILI participants reported drinking alcohol at a mean±SD of 2.7±2.1 annual assessments, which did not differ (p=0.64) from the 2.7±2.2 timepoints reported by DSE participants. Randomization arm did not have a main effect on alcohol trajectory (p=0.16). A similar percentage of participants reported abstaining from alcohol at all annual assessments in the ILI (29.4%) and DSE groups (31.4%). ILI and DSE participants did not differ in the percentage of participants who endorsed inconsistent drinking (35.7% vs 32.1%, respectively), or those who reported consistently drinking at a light (28.4% vs 29.4%), moderate (4.6% vs 5.2%), or heavy amount (1.9% vs 2.0%).

ILI

Weight.

In the ILI group, alcohol consumption trajectory did not have a main effect on weight loss at year 1 (ps>0.05; Figure 1). ILI participants who abstained from alcohol lost a mean±SE of 8.9±0.3% of initial weight at year 1, which did not differ significantly (p=0.99) from the 9.1±1.2% lost by participants who drank a heavy amount. Participants who drank only at baseline lost 9.1±0.5% and those who drank only at year 1 lost 8.2±0.7%. Relative to participants who were abstinent from alcohol, participants who drank at baseline and year 1 lost a similar amount regardless if they drank a light (8.9±0.3%, p=0.29), moderate (9.7±0.7%, p=0.40), or heavy amount (p=0.99).

At year 4, ILI participants who abstained from alcohol consumption over the 4 years lost 1.6±0.5% more weight compared to individuals who drank alcohol at any time over the 4 years (p=0.003). ILI participants who abstained from alcohol (over the 4 years) lost 5.1±0.3% of initial weight at year 4, compared to significantly (p=0.04) smaller loss of 2.4±1.3% for participants who weres consistent-heavy drinkers (Figure 2). The weight losses of participants who were abstinent from alcohol were significantly larger than the 3.8±0.3% losses of participants who drank inconsistently (p=0.01) and 4.2±0.4% losses of those who were consistent-light drinkers (p=0.047). Participants who were consistent-moderate drinkers lost 3.7±0.9%. Weight loss for consistent-heavy drinkers was not significantly different compared to those who were inconsistent (p=0.28), consistent-light (p=0.19), or consistent-moderate drinkers (p=0.40).

Figure 2. — Percent reduction in initial weight at year 4 in the intensive lifestyle intervention group by alcohol consumption trajectory over the 4 years. Values shown are mean (± standard error), and weight losses were estimated by using linear mixed‐effects models controlling for baseline age, race/ethnicity, gender, education, smoking status, BMI, insulin use, diabetes duration, depressive symptoms, and physical and mental health-related quality of life.

At year 4, meeting a categorical weight loss of ≥10% differed by alcohol trajectory group (p=0.002; Figure 3a). The percent of participants who achieved ≥10% weight loss was significantly higher than expected in the abstainer group (27.5%). In the consistent heavy drinker group only two participants achieved a ≥10% weight loss (4.8%). The percent of participants who achieved this weight loss was 22.6% of inconsistent drinkers, 22.9% of consistent-light drinkers, and 16.0% of consistent-moderate drinkers. Categorical weight losses differed by alcohol consumption trajectory for the achievement of a ≥5% (p=0.01) loss of initial weight. The alcohol abstainer group had 52.4% of participants who met a 5% weight loss, compared to 44% of inconsistent drinkers, 44% of consistent-light, 41% of consistent-moderate drinkers, and 33.3% of consistent-heavy drinkers.

Diet.

In exploratory analyses with the subgroup of participants with data from the food frequency questionnaire, each alcohol trajectory group had significant within-group declines in dietary calories from baseline to year 1 and baseline to year 4 (ps<0.05; Figure 5a). Change in dietary intake did not differ by alcohol trajectory group (ps>0.05). At year 4, relative to those who were abstinent from alcohol, inconsistent drinkers reported an additional mean±SE of 28.8±50.4 kcals/day (p=0.57), consistent-light drinkers 182.8±51.9 kcals/day (p<0.001), consistent-moderate drinkers 188.9±110.0 kcals/day (p=0.09), and consistent-heavy drinkers 81.4±150.6 kcals/day (p=0.59). At year 4, the average reported kcals/day of alcohol ingested by inconsistent drinkers was 4.7±1.4, consistent-light drinkers was 21.5±1.4, consistent-moderate drinkers was 79.4±4.0, and consistent-heavy drinkers was 139.5±5.7.

Figure 5. — Mean self-reported daily caloric intake at baseline, and years 1 and 4 based on 4-year alcohol trajectory in the (a) intensive lifestyle intervention and (b) diabetes support and education groups. Error bars represent the standard error. Grey bars represent non-alcoholic dietary intake. Black bars represent calories from alcohol. *p<0.05 for difference relative to abstinent group in total dietary intake value at baseline, year 1, or year 4. ^p<0.05 for differences relative to abstinent group in non-alcohol dietary intake. The amount of change in total dietary intake from baseline to year 1 and baseline to year 4 did not differ significantly by alcohol trajectory group (ps>0.05). ILI: Each alcohol trajectory group had significant within-group declines in dietary intake from baseline to year 1 and baseline to year 4 (ps<0.05). DSE: Each group had significant declines dietary intake from baseline to year 1 with the exception of the consistent-moderate group which was not significant for either.