Review of common weight loss diets

September 15, 2016

Karmella Thomas, RDN, LD,CDE

Development of Obesity

• “Obesity can develop only from an excess of energy intake over expenditure.”

» N Engl J Med 1997;337:396-407

• For weight loss, only calories count.” N Engl J Med 2009;360:859-873

• “Calories alone account for increases in body fat.”

JAMA 2012;307(1):47-55

Disconnect:

Lack of Understanding of the Relationship Between

Calories and Weight Gain Exists

• 70% of Americans do not believe calories cause weight

gain

• Only 12% could accurately estimate the calories of foods

• More than 80% of those watching their weight don’t

watch their calories

• 90% don’t know their calorie budget.

2009, 2010, 2011 Food and Health Survey USDA

www.encha.com/fat-cell-development

Obesity Treatment Guidelines

Treatment

BMI Category

25-26.9 27-29.9 30-34.9 35-39.9 >40

Lifestyle Therapy* With

Comorbid.

With

Comorbid. YES YES YES

Pharmacotherapy With

Comorbid. YES YES YES

Surgery With

Comorbid. YES

Lifestyle therapy - diet, physical activity, and behavioral

therapy - is the cornerstone of obesity treatment

*Consider pharmacotherapy only if a patient has not lost 1 pound per week

after 6 months of combined lifestyle therapy.

Low Carbohydrate/High Protein Diets

• Paleo Diet

• Atkins Diet

• Ketogenic Diet

Paleo Diet

•Typically 23% Carbohydrates, 38% protein,

and 39% fat

•Can vary depending upon preference

•Have ‘EAT” foods and “Don’t EAT” foods

• Restrict cereal grains, legumes, dairy, potatoes, salt, refined sugar and oils, “processed” foods

Atkins • Very low carbohydrate diet

• “Flip the body’s metabolic switch” from burning carbs to burning fat

•Has 4 phases of gradual increased carb intake for

each phase

•Phase 1: 20 grams of carbs per day

•Phase 2: 25 grams of net carbs per day

•Phase 3: 25 grams + 5-10 grams of carbs more/day

•Phase 4: 25 g (more or less) personal preference

Atkins 40 Plan

The A to Z Weight Loss Study: Randomized Trial

•Compared 4 weight loss diets (low to high carb

intake) and effect on weight loss and metabolic

variables in 1 year’s time

•12 month randomized trial with 311

overweight/obese women (premenopausal,

nondiabetic) with BMI between 27-40

•Atkins, Zone, LEARN, Ornish diets

•Weekly instruction for 2 months and additional 10

month follow up JAMA. 2007;297(9):969-977. doi: 10.1001/jama.297.9969

Diets

•Atkins: 20g/d or less for first 2-3 months and

then 50 g/day or less for ongoing weight loss

phase

•Zone: 40% carbs, 30% protein, 30% fat

•LEARN: 55%-60% carbs, 10% fat, calorie

restriction, increased exercise, and behavior

modification

•Ornish: 10% or less calories from fat, physical

activity, behavior modification

Results

•At the 2 and 6 month intervals, the Atkins group had

significantly greater weight loss than all groups –Weight loss between ZONE, LEARN and Ornish did not differ

significantly at any time

• Body fat and waist-hip ratio did not achieve statistically significance between groups

•Only HDL and triglycerides findings were significant

and favored Atkins group

•LDL changes favored LEARN and Ornish diets at 2

months but differences diminished at 6 & 12 months

Concerns… •What does 20 grams per day or less of

carbohydrates look like?

•1 – 1.5 oz of bread

•1-2 cups of fruit

•1/3 cup of rice or pasta

•3 cups of popcorn

• ½ cup of ice cream

Ketogenic Diet

•Ketosis is a metabolic state that occurs when

dietary carbohydrates are in such low quantities

that your body relies almost exclusively on fatty

acid oxidation and ketone metabolism to

produce ATP

•Used for Dementia and Epilepsy in Medical

Nutrition Therapy –Developed by Dr. Russell wilder at Mayo Clinic in 1924

The basics

• Intention to put the body into ketosis

•70% calories from fat, 25% protein, 5% carbs

•2,000 calorie diet = 20 g carbs, 155g fat and

125g protein

• “Meals should be protein, veggies, and extra side of fat”

• “Just be sure to know that the first week usually gives you some killer headaches and lethargy…”

Calorie for calorie, dietary fat restriction results in

more body fat loss than carbohydrate restriction in

people with obesity. Hall, Kevin D, et al.

•Inpatient metabolic balance study

•Examine the effect of selective isocaloric

reduction of dietary carbs vs fat on body

weight, energy expenditure, and fat balance

•Small study (19 obese adults)

–10 males and 9 females

Cell Metab. 2015 September 1; 22(3):427-436. doi:10.1016/j.cmet.2015.07.021

Cell Metab. 2015 September 1; 22(3):427-436. doi:10.1016/j.cmet.2015.07.021

Cell Metab. 2015 September 1; 22(3):427-436. doi:10.1016/j.cmet.2015.07.021

Cell Metab. 2015 September 1; 22(3):427-436. doi:10.1016/j.cmet.2015.07.021

Results

• Experimental diets were 30% lower in calories than baseline

diet (carb and fat varied, protein stayed same)

• The carb restricted diet led to decreased insulin secretion

and increase in net fat oxidation but fat restricted diet did not

• Both diets resulted in body fat loss, but the reduced fat diet

led to significantly more fat loss than the reduced carb diet

• Concluded that reducing dietary fat can lead to greater body fat loss than reducing dietary carbs in adults with obesity

US News and World Reports

•Best Weight-Loss Diet

#1 Weight Watchers

#2 HMR Program (Health Management Resources)

#3 Biggest Loser Diet

•New Category this year – Best Fast Weight

Loss Diet

–HMR program and Biggest Loser (tie for 1st)

Weight Watchers

• New SmartPoints® plan

– No food is off limits

– Each food is given a number based

upon calories, saturated fat, sugar, and

protein

• Online Plus

• Meetings

• Personal coaching

Randomised controlled trial of four commercial weight

loss programmes in the UK: initial findings from the

BBC “diet trials”

• Compared Atkins, Slim Fast, Weight Watchers, and

Rosemary Conley’s eat yourself slim diet and fitness

plan

• Measured weight and body fat changes over 6 months

• Similar weight loss among diet groups compared to

control

• Average weight loss of 5.9 kg and average fat loss of 4.4

kg

BMJ. 2006 Jun 3; 332(7553): 1309–1314.

BMJ. 2006 Jun 3; 332(7553): 1309–1314.

Weight Watchers

•2015 introduced Beyond the Scale

Program

•Emphasizes 3 components:

–Eating healthier

–Fitness that fits your life

– “developing the skills and connections to

tune in and unlock inner strength”

Biggest Loser Diet

• Six weeks of healthy food & regular exercise

• 4-3-2-1 Pyramid

– 4 servings of fruits and vegetables

– 3 servings of lean protein

– 2 servings of whole grains

– 200 calories of “extras” (desserts)

• Exercise at a high level

• Some meal plans go below 1,200 calories/day

Weight Loss Results

•2011 American Journal of Medicine study

•Small – 14 Biggest Loser contestants

•7 months of intense exercise and reduced calorie

diet (moderate)

•Lost average of 133 pounds (39% of initial weight)

• Improvements in atherosclerosis risk, carotid

vascular function, lipids, insulin resistance, and

inflammatory biomarkers Am J Med. 2011 Oct;124(10):978-82. doi: 10.1016/j.amjmed.2011.02.032. Epub 2011 Jul 27.

Meal Replacements

• Meta and pooling analysis from 6 studies on safety and

effectiveness of partial meal replacements (1 or more

meal replacements per day) for long term weight

management

• 800 to 1,600 calories/day using meal replacements and

other healthy foods for at least 3 months in overweight

adults compared to conventional reduced calorie diet

• International Journal of Obesity (2003) 27, 537–549.

doi:10.1038/sj.ijo.0802258

Results •6 data sets produced 249 meal replacements

subjects and 238 control subjects

•46 years old, 75% women and mean BMI of 31

kg/m2 (119 had type 2 diabetes)

•Weight loss was significant in both groups, but

greater in the meal replacement group

• At 3 months, meal replacement group lost 7% of weight compared to 4% in reduced calorie diet

–Sustained at the 1 year mark

HMR Program

• In-clinic and at-home program options

• 200 different clinics (one located here at UNRSOM)

• Meal Replacements and Physical Activity

• 2 diet options (More is Better strategy)

– Decision Free (5 shakes per day)

– Healthy Solutions (3 shakes + 2 Entrees + 5 c

V/F)

Other meal replacement diets

• Slim Fast

• Jenny Craig

• Nutri-system

• Optifast

What does it come down to?

•What will the patient do?

•What medications are they on?

•What can they do now, but also in 6

months?

•What does their support look like?

THANK YOU!