Macronutrient Carbohydrate

8/2/2019 Macronutrient Carbohydrate

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Introduction to Macronutrientsand Nutritional Assessment

Virginia E. Uhley, PhD, RD

Integrative [email protected]


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INTRODUCTION

Nutrition:

The science of food, nutrients, and the

substances therein, their action, interaction,and balance in relation to health and disease,

and the process by which the organism

ingests, digests, absorbs, transports, utilizes,

and excretes food substances.

AMA, Council on Food and Nutrition


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Chronic Disease Prevention and

Diet

Poor dietary intake is linked to leading

causes of adult deaths:

heart disease

stroke

hypertension

diabetes

cancer


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Famous Quote

If we could give every individual the right

amount of nourishment and exercise, not

too little and not too much, we would havefound the safest way to health.

Hippocrates c. 460-377 B.C.


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Macronutrients

Carbohydrates

Proteins

Fats (lipids)


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Major Functions of

Macronutrients

Provide energy (kcalorie)

Kcal: measure of the amount of heat needed to

raise the temperature of 1000 grams (1 liter) ofwater to 1 degree C. (approximately the same

as 4 cups of water to 2 degrees F)


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Major Functions of

Macronutrients, cont

Important for growth and development

Act to keep body functioning normally


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Definitions

Deficiency: lack of nutrients

biochemical deficiency symptoms

nutrition deficiency symptoms measured in blood orurine (such as low levels of a nutrient or enzyme

activities)

clinical symptoms appear as a result of severe or

prolonged lack of nutrients (changes seen in physical

examination in skin, hair, nails, tongue, and eyes.


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Definitions, cont

Overnutrition: nutritional intake exceeds

needs.

Undernutrition: nutritional intake falls

below needs to maintain health, results

from long-term reductions in nutrients.


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Nutritional Assessment

5 components

A. Anthropometry

B. Biochemical

C. Clinical Examination

D. Dietary Evaluation

E. Energy Expenditure (Physical Activity)


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Diet History

24-hour recall

Food Frequency

Usual Intake

Food Record


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24-Hour Recall

Documents a patients intake of all food and

beverages during the previous 24-hour period.

Many patients do not remember what they ate andcan not accurately estimate quantities

consumed.

Ideal for patients with diabetes-ability to assess

timing of meals, snacks, and insulin injections


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Food Frequency Method

Estimate the frequency and quantity of foods

eaten during a weekly or monthly period.

Ideal method to estimate fat, sodium, sugar, dairy,fruit and/or vegetable intake.

Ideal for patients with CVD, HTN, osteoporosis,

those that question whether they should take a

vitamin supplement, and elderly who avoid food

groups.


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Usual Intake Method

Documents a patients usual intake, including

breakfast, lunch, dinner, and snacks.

Many patients are not consistent with their eatinghabits and state that that there is no usual

pattern.

Ideal for elderly patients in order to assess

number of meals eaten (or skipped), and infants,

children, and adolescents whose diets may not be

as varied.


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Food Record Method

Written record by the patient of everything they ate and

drank over a 2 to 7 day period.

Many patients are not motivated to write down everything.

(although those who do, may lose weight.)

Difficult for physicians to take the time to review and

comment, especially if not trained.

Ideal for patients who have difficulty losing weight, those

who are eating out of control and gaining weight, brittle

diabetics, emotional eaters.


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Assessing Nutrient Intake

Assess energy requirements via Harris

Benedict Equation.

Compare current caloric intake with

calculated requirements.


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Estimation of Resting Energy

Requirements (REE)

Harris Benedict Equation

derived from healthy adults

calculates resting energy expenditure

additional stress and activity factors added

REE for males: 66+[13.7 x wt (kg) ] + [5.0 x ht

(cm) ] - [6.8 x age] = kcal/day REE for females: 655 + [9.7 x wt (kg)] + [1.8 x ht

(cm)] - [4.7 x age] = kcal/day


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Calculation to Estimate Caloric

Needs to Maintain Body weight

(Current Weight, in lbs) x (A) = Daily Caloric

Needs.

A= activity level

Not very active 12

Moderately active 15

Very Active 20Extremely Active 25


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Calculation for Estimate of Basal

Metabolic Rate

Men = 1 x body weight (kg) x 24

Women = .9 x body weight (kg) x 24

calculates basic expenditure of calories in

a 24 hour period.


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Assessment of Nutrient Intake

Dietary Reference Intakes (DRIs)

Reference values that are quantitative of nutrientintakes to be used for planning and assessing diets forhealthy people.

Recommended Dietary Allowance(RDAs)

Recommended nutrient intakes that meet the needs ofessentially all people of similar age and gender.

Estimated Average Requirement (EARs) Estimated nutrient intakes that meet the needs of

essentially all people of similar age and gender.


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Assessment of Nutrient Intake,

cont

Adequate Intakes (AIs)

Adequate intake to maintain health

Estimated Energy Requirements (EERs) Set for daily energy requirements based on

defined levels of activity (Different from RDA)

Upper levels (ULs) The maximum level of daily nutrient intake thatis likely to pose no risk or adverse effects


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Current American Dietary

Guidelines

Recommendations:

55% of total kcals to come from carbohydrates

Sugars no more than 10%

15% of total kcals to come from proteins

30% or less to come from fat


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ADA exchange system

Designed as a quick way to estimate total kcals,

carbohydrate, protein, and fat intake.

Six different categories: milk

fruit

vegetables

starch/bread

meat

fat


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Milk (serving size 1 cup)

Carbohydrate

(grams)

Protein

(grams)

Fat

(grams)

Kcalories

12 8 Skim: trace

Lowfat: 5

Whole: 8

90

120

150


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Fruit (serving size 1 small)

Carbohydrate

(grams)

Protein

(grams)

Fat

(grams)Kcalories

15 60


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Vegetable (serving size -1 cup)

Carbohydrate

(grams)

Protein

(grams)

Fat

(grams)

Kcalories

5 2 25


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Starch/Bread (1 slice, c raw, cooked)

Carbohydrate

(grams)

Protein

(grams)

Fat

(grams)Kcalories

15 3 Trace 80


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Meat (1 ounce)

Carbohydrate

(grams)

Protein

(grams)

Fat

(grams)

Kcalories

0 7 Lean: 3

Medium: 5High: 8

55

75100


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Fat (1 teaspoon)

Carbohydrate

(grams)

Protein

(grams)

Fat

(grams)

Kcalories

5 45


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Exchange food patterns (totalKcals: 55% CHO, 30% fat, 15% protein)

Kcal/day 1200 1600 2000 2400 2800

Exchange group

Milk (lowfat) 2 2 2 2 2

Vegetables 2 2 3 3 3

Fruit 5 4 5 8 8

Starch/Bread 4 8 11 11 15

Meat (medfat) 2 2 3 5 5

Fat 4 7 8 9 12


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Food Guide Pyramid

Food Group Serving Major

contributions

Foods/

Serving

sizes

Milk,

yogurt,

And cheese

2 adult

3 children,

Pregnantor

lactating

women

Carbohydrate

Calcium

RiboflavinProtein

Potassium

Zinc

1 C milk

11/2 oz

cheese

1 c yogurt

2 cups

cottage

cheese


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Food Guide Pyramid, cont


contribution

s

Foods/

Serving

sizes

Meat,

poultry,

fish, dry

beans,eggs,

nuts

2 -3 Protein

Niacin, Iron

Vitamin B6,

B12

Zinc

Thiamin

2-3 oz cooked

meat

1-1 c cooked

dry beans2 T peanut

butter

2 eggs

-1 c nuts


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contributions

Foods/

Serving

sizes

Fruits 2 - 4 Carbohydrate

Vitamin C

Dietary Fiber

c dried

c cooked

cup juice

1 small

1 melon

wedge


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contributions

Foods/

Serving

sizes

Vegetables 3 - 5 Carbohydrate

Vitamin A

Vitamin C

Folate

Magnesium

Dietary fiber

c raw or

cooked

1 c raw leafy


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contributions

Foods/

Serving

sizes

Bread,

Cereal,

Rice,

Pasta

6-11 Carbohydrate

Thiamin

Riboflavin

Iron, NiacinFolate, Zinc

Magnesium

Dietary Fiber

1 sl bread

1 oz dry cereal

-3/4 c cooked

cereal,

rice,pasta

3-4 small

crackers


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contributions

Foods/

Serving

sizes

Fats, Oils,

And Sweets

Based on

individual

energy

needs.

Foods from

this group

should not

replace any

from the other

groups.

Use

sparingly

F d G id P id ADA


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Food Guide Pyramid vs ADA

Exchange List

Food Guide Pyramid

recommendations

based onapproximately 2,500

kcal intake/day

based on nutrient

needs

(vitamins/minerals)

ADA Exchange List

lists based on total

kcal intake based on modulating

carbohydrate, protein,

and fat intake


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Carbohydrates

Simple:

monosaccharides - glucose, fructose,

galactose disaccharides

sucrose: (table sugar) glucose + fructose

lactose: (milk sugar) glucose + galactose

Maltose: ( malt sugar) glucose + glucose


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Carbohydrates, cont

Complex Carbohydrates:

polysaccharides: amylose, glycogen

Starch, composed of many glucose molecules

Dietary fiber (nonstarch polysaccharides):

Insoluble - lignins, cellulose, hemicellulose

basically insoluble in water, not metabolized by intestinal

bacteria.

Soluble - pectins, gums, mucilages


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M j f ti f


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Major functions of

Carbohydrates

Supply energy: 4 kcal/gram

Brain, nerve cells, and red blood cells require glucosefor energy

Storage form: Glycogen in liver (adult: ~ 120 g) andmuscle (


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Carbohydrate functions, cont

Protein sparing

Prevents lean body mass from being used for

energy

Antiketogenic 50-100 g carbohydrate/d


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Key roles of Dietary Fiber


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Key roles of Dietary Fiber

Insoluble fiber: increases fecal bulk,

decreases intestinal transit time.

Soluble fiber: delays stomach emptying;slows glucose absorption; can lower blood

cholesterol level.


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Example of a 25-gram Fiber Diet (1500

Kcal)

Breakfast Fiber g

Orange Juice,1 c

Wheaties, c 3.0

1% Milk, 1/2c

Whole Wheat toast, 1 sl 1.9

Coffee

Lunch

Lean turkey

Whole Wheat bread, 2 sl 3.8

Baked Beans, 1/2c 3.5

Mayonnaise,2 tsp

Lettuce, c 0.2

Pear, with skin 4.3


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25 g Fiber Diet, cont

Dinner Fiber g

Broiled chicken (no skin), 3oz

Baked Potato, with skin, 1 lg 3.6 Margarine/butter, 1 1/2tsp

Green Beans, 1 c 2.0

1% milk, 1 c

Apple, with peel,1 med 3.0

Total fiber grams = 25


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Carbohydrate Recommendations

RDA: 130 g/day for adults

50-100 g/day to prevent ketosis

1 orange juice = 25g, 1 apple = 20

DRI: 45-60% from total Carbohydrate

Fiber: general recommendation 20-35

grams/day

New guidelines:

Under 50 yrs old: Men 38 g/day, Women 25 g/day

Over 50 yrs old: Men 30g/day, Women 21 g/day


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Calculation of Dietary Intake of


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Calculation of Dietary Intake of

Carbohydrate Kcals

1). Calculate total grams of Carbohydrate

intake.

Note: did you meet the RDA?

Note: did you consume 50-100 g and prevent

ketosis?

2). Multiply total grams of carbohydrate x4= total kcals of carbohydrate intake

Popular Low Carbohydrate


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Popular Low-Carbohydrate

Weight loss diets

Most common form

Forces depletion of body stores to provide

glucose to needed cells such as red bloodcells.

Forces depletion of muscle and other leantissues to provide carbons for glucose.

Water is lost rapidly (as glycogen storesare depleted)


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Examples of Low Carbohydrate


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Examples of Low-Carbohydrate

Diets

Dr. Atkins, Dr. Stillman, Calories dont

Count, Scarsdale Diet, Drinking mans diet,

Four day wonder diet, Air Force diet, SugarBusters, The zone, etc.


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Historical Low-Carbohydrate Diet

William Banting

Letter on Corpulence, 1864.

William Harveys 1872 publication On

corpulence in relation to disease, with some

remarks on diet.


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Typical Menu

Breakfast: 4-5 ounces of beef, mutton, kidneys, broiled fish, bacon, or cold meat

of any kind but pork.

1 small biscuit or 1 ounce of dry toast, 1 large cup tea without milk or sugar.

Lunch: 5-6 ounces of any fish except salmon, any meat except pork, anyvegetable except potato

Any kind of poultry or game. 1 ounce of dry toast. Fruit 2-3 glasses of good

claret, or sherry. 2-3 ounces of fruit. 1-2 rusks (cut from bread and re-

baked). 1 cup tea without milk or sugar.

Supper: 3-4 ounces of any meat except pork, any fish except salmon, 1-2

glasses of claret.

Night-cap: 1 tumbler of grog(gin, whiskey or brandy without sugar added)

or 1-2 glasses of claret or sherry.


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Current Research Evidence

A Randomized Trial Comparing a Very Low

Carbohydrate Diet and a Calorie-restricted

Low-Fat Diet on Body Weight andCardiovascular Risk Factors in Healthy

Women.

Brehm BJ et al, J Clinical Endocrinology &Metabolism, 2003


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Study Design

53 Women were randomized to a diet

intervention group for 6 months

27 to a calorie-restricted low fat diet (30 %)

26 to a ad libitum very low carbohydrate diet

Maximum intake of carbohydrates to be 20 g/dAfter 2 weeks, could increase to 40-60 g/d only if

self-testing urinary ketones indicated ketosis.


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Study inclusion Criteria

At least 18 yrs of age

Moderate obesity (BMI 30-35)

BMI = weight (kg)/height (m)2

Stable weight over the past 6 months

No weight loss or gain > 10% of their body

weight


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Study Exclusion Criteria

Cardiovascular Disease

Untreated hypertension

Diabetes

Hypothyroidism

Substance abuse

Pregnancy or lactation


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Results

Women on both diets reduced caloric intake bycomparable amounts at 3 and 6 months.

Decreased by approximately 450 calories.

The very low Carbohydrate diet group lost moreweight than the low fat diet group.

(8.5 + 1.0 vs.3.9 + 1.0 kg; P


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Results, cont

No differences in mean levels of blood pressure,

blood lipids, fasting glucose, insulin, all were in

normal ranges. At 3 months the Very low carbohydrate diet group

was consuming a mean level of 1156 Kcal/d, 15%

Carbohydrate, 28 % protein, 57% fat.

At 3months the Low fat diet group was consuminga mean level of 1245 Kcal/day, 54% carbohydrate,

18% protein,and 28 % fat.


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Conclusions

A very low carbohydrate diet is more effectivethan a low fat diet for short term weight loss, andover six months is not associated with

deleterious effects on important cardiovascularrisk factors in healthy women.

The gradual increase in carbohydrates in the verylow carbohydrate diet group after 3 months

suggests recidivism is likely in persons followingthis diet, long term weight maintenance may bedifficult.


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A Low-Carbohydrate as Compared to a Low-

Fat Diet in Severe Obesity.

Samaha FF. et al, NEJM, 2003


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Study Design

132 severely obese subjects (including 77 blacks

and 23 women)

Mean BMI: 43, with high prevalence of diabetes(39%) or metabolic Syndrome (43%).

Were randomly assigned to either a carbohydrate

restricted diet (low-carbohydrate) (n= 64) or a

calorie and fat restricted diet (low-fat diet) (n=68)

for 6 months.


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Study Design, cont

Subjects on the low carbohydrate diet wereinstructed to consume 30 g or less/day ofcarbohydrate.

Vegetables and fruits with high ratios of fiber tocarbohydrate were recommended.

Subjects the low fate diet were instructed toconsume 30 % or less/day of their total Kcal

intake as fat and to reduce their total Kcal intakeby 500 Kcals.

Followed Obesity Guidelines from NHLBI.


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Inclusion Criteria

Age at least 18 yrs

BMI: of at least 25.


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Exclusion Criteria

Serum creatinine level of more than 1.5mg/deciliter

Hepatic diseaseSevere,life-limiting medical illness.

Inability of diabetic subjects to monitor

their own glucose levelsActive participation in a dietary program

Use of weight loss medications.


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Study Results

79 subjects completed the 6 month study,

Low-fat group = 36

low carbohydrate group =43

The low carbohydrate diet group lost more weightthan the low-fat group

Mean [+ SD]5.8+8.6 kg vs. -1.9+4.2 kg,P=0.002

The low carbohydrate diet group had greaterdecreases in triglyceride levels

Mean -20+43 % vs -4+31%;P=0.001


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Study Results, cont


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Results, cont

Insulin sensitivity, measured only in those

subjects without diabetes, improved more

in the subjects on the low carbohydratediet than those on the low fat diet.

6+9% vs -3+8%; P=0.01

Serum glucose levels were markedlyreduced in the low carbohydrate diet group

compared to the low fat group.


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Conclusions

Severely obese subjects with a high prevalence

of diabetes or metabolic syndrome lost more

weight on the low carbohydrate diet.

Overall, there was only a small magnitude of

difference in weight loss between the two diet

groups, so longer studies are needed to

evaluated the impact on cardiovascular disease.


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Efficacy and Safety of Low-Carbohydrate

Diets: A systematic review.

Bravata DM et al, JAMA, 2003.


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Study Design

Included articles describing adult, outpatient

recipients of low carbohydrate diets of 4 days or

more in duration, and 500 kcal/d or more

(carbohydrate content and total calories

consumed had to be reported)

107 articles describing 94 dietary interventions

reported data for 3268 participants; 663 receiveddiets of 60 g/d or less of carbohydrate, of which 71

received 20 g/d or less of carbohydrates.


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Results

No study evaluated diets of 60 g/d or less for

participants with a mean age older than 53.1 yrs.

Only 5 studies ( nonrandomized and nocomparison group) evaluated these diets for

more than 90 days.

Among obese patients, weight loss was

associated with longer diet duration, restrictionof caloric intake, but not with reduced

carbohydrate content.


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Results, cont

Low carbohydrate diets had not significant

adverse effects on serum lipids, fasting

serum glucose, fasting insulin levels,orblood pressure.


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Conclusions

There is insufficient evidence to makerecommendations for or against the use of lowcarbohydrate diets, particularly among

participants older than 50 yrs, for use longer than90 days, or for diets of 20 g/d or less ofcarbohydrates.

Among the published studies, participant weight

loss while using low carbohydrate diets wasprincipally associated with decreased caloricintake and increased diet duration but not withreduced carbohydrate content.


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