Chap 6.2 proteins

NTR 306: Fundamentals of Nutrition

Chapter 6: Proteins

Part II

Overview of Protein Requirements

  • Protein DRIs & Habitual Intake

    • Protein amounts within Acceptable Macronutrient Distribution Range (AMDR) for a 2000 kcal diet:

    • Lower Range:

      • 2000 ext{ kcal} imes 0.10 = 200 ext{ kcal}

      • 200 ext{ kcal} / 4 ext{ kcal/g} = 50 ext{ g/d}

    • Upper Range:

      • 2000 ext{ kcal} imes 0.35 = 700 ext{ kcal}

      • 700 ext{ kcal} / 4 ext{ kcal/g} = 175 ext{ g/d}

  • The Recommended Dietary Allowance (RDA) is set to prevent negative nitrogen balance, which is essential for growth, development, and maintenance needs.

  • AMDR (lower range) includes whole-body protein requirements, as indicated by RDA.

  • No Tolerable Upper Intake Level (UL) for protein as it is not toxic.

  • AMDR (upper range) reflects protein intake after considering carbohydrates (CHO) and fats.

Total Protein DRIs for Adults

  • DRIs for Adults:

    • Males:

    • RDA: 0.8 ext{ g/kg body weight/d}

    • 56 g/d average intake

    • AMDR: 10-35% of total calories

    • No established UL

    • Females:

    • RDA: 46 g/d

    • AMDR: 10-35% of total calories

    • No established UL

  • Assumptions:

    • Healthy individuals

    • Energy intake is adequate

    • Protein sources are high quality

    • Sufficient carbohydrates and fats are consumed

  • For Adults aged 19-30 years:

    • 0.8 ext{ g/kg} = 0.36 ext{ g/lb}

Habitual Protein Intakes

  • Habitual Intakes for Adults:

    • Males:

    • 1.0 g/kg body weight/d

    • 98 g/d intake average

    • 15% of total calories

    • Females:

    • 71 g/d intake average

Instapoll on Protein Recommendations

  • Are we meeting DRI recommendations? Possible answers:

    • No, we are below the RDA

    • No, we are above the RDA but exceed the UL

    • Yes, we meet RDA and are within AMDR (no UL established)

    • There are no DRIs for protein

Dietary Guidelines for Americans (DGAs) for Protein

  • Recommendations:

    • Consume a variety of protein-rich foods:

    • Seafood

    • Lean meats, including red meats, lean poultry, eggs

    • Legumes (beans and peas), nuts & seeds, soy

    • Limit consumption of:

    • Fatty and/or processed meats

  • Key Assumptions:

    • All protein sources are equivalent

    • All meats are equivalent

    • Addressing message accuracy regarding protein sources

Health Risks Associated with Protein Excess

Cardiometabolic Risks

  • Findings:

    • No causal link between increased protein and cardiovascular disease (CVD) risk

    • No causal link between increased protein and type 2 diabetes risk

    • Many protein-rich foods beneficial for heart health include:

    • Fruits

    • Nuts

    • Fish

    • Vegetables

    • Vegetable oils

    • Whole grains

    • Beans

    • Yogurt

    • Eggs, poultry, dairy, lean meats

    • Harmful foods include:

    • Refined grains

    • Starches, sugars

    • Fatty and processed meats

    • High sodium foods

    • Trans fats

Cancer Risks

  • Findings:

    • No direct causal relationship between increased protein and cancer

    • Processed and fatty meat consumption associated with increased risks of CVD and various cancers

Discussion on Red & Processed Meats

Breakout Chat Activity

  • Discussion on what specifically increases health risks associated with red and processed meats.

Chat Debrief on Meat Health Risks

  • Factors influencing meat’s health risks:

    • Protein content

    • Saturated fat content

    • Accompanying foods (e.g., fries, refined grains)

    • Cooking or processing methods

Dairy Recommendations in DGAs

  • Low-fat (1%) or fat-free alternatives (1 cup equivalent per day based on caloric needs):

    • Calories, saturated fat, protein, added sugar for different dairy products are detailed.

    • Low-fat (1%): 100 calories, 1.5g saturated fat, 8g protein, 0g added sugar

    • Fat-free (Skim): 80 calories, 0g saturated fat, 8g protein, 0g added sugar

    • Lactose-free options are comparable

    • Soymilk (unsweetened): 80 calories, 0g saturated fat, 7g protein, 0g added sugar

Protein Foods in DGAs

  • Recommendations on protein food groups for a healthy US dietary pattern include:

    • Protein intake (oz equivalent per day):

    • 2 oz at 1,000 caloric level

    • 5-6 oz at 2,000 caloric level

    • Sources: Lean meats, poultry, eggs, seafood, nuts, seeds, and soy

Optimizing Protein for Health Benefits

Well-being

  • Roles of dietary protein in:

    • Weight management across the lifespan

    • Muscle strength and physical performance

Muscle Gain & Strength

  • Increased dietary protein linked to increased muscle mass and strength through resistance training

Weight Management Effects

  • Increased dietary protein during energy restriction enhances weight and fat loss while preserving muscle

  • Helps prevent weight regain after weight loss

  • Increases appetite control and satiety by affecting hunger cues and cravings

Questions to Consider

  • What constitutes your optimal protein intake?

    • Process for determining protein intake based on body weight and meal frequency discussed

Protein Quality

  • Protein deficiencies and considerations of:

    • Digestibility and amino acid composition

    • Animal proteins are typically more complete (higher digestibility 90-99%)

    • Plant proteins may lack one or more essential amino acids (70-90% digestibility)

    • Quality scores like Digestible Indispensable Amino Acid Score (DIAAS)

Protein Supplements

  • Most individuals can meet RDA through dietary sources alone.

  • Supplements are recommended to help build/maintain lean mass, particularly for those on vegan diets, to achieve adequate protein intake.

    • Typical protein supplement yields 24-30g of high-quality protein

Wrap-up & Reminders

  • Upcoming topics in lectures include Lipids.

  • Further assignments and discussion board participation mentioned, with deadlines noted.