Prof. John H. Muyonga

Presented at NatureUganda Event, 6th Feb 2014

FOOD PRODUCTS: THE PROS AND CONS TO OUR HEALTH AND

ENVIRONMENT

FOCAL ISSUES

Human food and nutrient requirements

Food intake and health

Food production and the environment

Suggestions for eating healthy while

conserving the environment

• Like air and water, food is essential for sustenance of life

• Food may however negatively impact on human health

Think

Function

Reproduce

Grow

Fight disease

Work

Repair self

Nutritional Requirements

The requirements of individuals depends on their sex, age, physiological condition, activity, health, among other factors

Age group Energy (Kcal/day)

Protein (g/day)

Men Women

Men Women

Early adult (18-65 years)

2900 2200 58 46

Later adults(65-85 years)

2300 1900 63 50

Pregnant - 2460 - 55

Lactating - 2570 - 68

FOODS SUPPLY NUTRIENTS REQUIRED BY HUMANS

LIPIDS

PROTEINS

VITAMINS AND MINERALS

ENERGY GROWTH AND REPAIR

CARBOHYDRATES

PROTECTION

WATER

Vari

ety

of

food is

requir

ed

by h

um

ans

Benefits of an adequate diet

Good nutriti

onHigh

resistance to

infection

Good health

Eating wellgood

appetite

• Higher productivity – physical & mental

• Better psycologically

• Slower aging – mental & physical

• Better reproductive outcomes

• Proper growth & development among children

Source: Adapted from RCQHC and FANTA 2003

Poor diets are injurious to health

Poor nutrition resulting in weakness, nutrient deficiencies

Increased nutritional needs, reduced food intake and increased loss of nutrients

Illness

Impaired immune system Poor ability to infections

Viscous cycle of malnutrition

Malnutrition Malnutrition/bad nutrition: Nutrients intake

less than (under nutrition) or more than (over nutrition) required.

Levels of Under-nutrition and Over-nutrition in Uganda: Children <5 years

UDHS

Over nutrition Intake of nutrients > body

needs Over weight is

associated with disease conditions such as diabetes, cancers, coronary heart diseasesBody mass index

(BMI)=Wt (kg)/ht (M sq)

Classification

< 18.5 Underweight

18.5-24.9 Healthy weight

25-29.9 Overweight

≥ 30 Obese

Over nutrition and disease burden Non-communicable (diet-related) diseases

associated with about;• 46 per cent of the global disease burden and • 60 per cent of all deaths worldwide

Cardiovascular disease alone amounted to 30 % of deaths.

The global burden of diet-related diseases is expected to climb to 57 per cent by 2020.

Food production & the environment Agriculture uses 40% of the world’s

land and 70% of its fresh water Encroachment on natural ecologies

including forests and wetlands Water polluted by nutrients, agro-

chemicals, pathogens and salts including phosphates and nitrates

Soil degradation and chemical alterations

Food production & the environment

Air Methane emission from

enteric fermentation and handling of manure

Ammonia volatilization from manure

Laughing gas emission related to decomposition of nitrogen

Carbon dioxide from burning of fossil fuel for energy production

Sulphur dioxide from fossil energy use

Biodiversity Loss

Loss and degradation of habitat fromclearing grasslands and forests anddraining wetland

Invasive species out competing natives

Killing of wild predators to protectlivestock

Loss of genetic diversity fromreplacing thousands of wild cropstrains with a few monoculture strains

Soil

Erosion

Loss of fertility

Salinization from irrigation

Desertification

Air & Climate

Greenhouse gas emissions from fossil fuel use

Other air pollutants from fossil fuel use

Pesticide drift from spraying

Dust / airborne particulates

Weather alteration from large scale clearing

Water

Aquifer depletion

Water diversions

Increased runoff andflooding from land clearedto grow crops

Sediment pollution fromerosion

Fish kills from pesticiderunoff

Surface and groundwaterpollution from pesticides, fertilizers & livestock

Overfertilization (eutrophication) of lakesand slow-moving riversfrom runoff of nitrates andphosphates fromfertilizers, livestockwastes, and foodprocessing wastes

Human Health

Nitrates in drinking water

Pesticides residues in drinking water,food, and air

Contamination of drinking andswimming water with disease organisms from livestock wastes

Bacterial contamination of meat

Farm worker exposure & working conditions

The food we eat and the environment

Ecological burden depends on resources required to produce

given food

Ecological burden of production depends on system used

Developments that have increased ecological burden of food production

Genetic selection and manipulation to enhance productivity

Increasing area farmed Dominance by a few crops

and animals Increased use of inputs,

including fertilizers, antibiotics & pesticides

Mechanization Food transportation over

longer distances More intensive & frequent

production Increased processing &

packaging

Salt production

Palm field

Palm normally planted in areas recently cleared of forests

Environmental concerns of sugar production

Approximately 145 million metric tons of sugar produced globally per annum

Sugarcane production associated with highest biodiversity loss than any other crop

Habitat destruction Intensive water use: Linked to

nearly drying up Zambezi, Niger, Indus and Mekong rivers

Heavy use of agro-chemicals Air and water pollution

Ecological burden of packaging

Waste water resulting from food processing

Food Vol (‘000l/ton)

Milk 9-18.1

Meat 13.6-18.1

Beer 9-14.5

A large food processing plant uses >4 million litres of potable water per day

One third of food produced is wasted Poor storage facilities, processing, packaging and

distribution infrastructure Poor production planning Premature harvesting High quality standards Abundance and consumer attitudes

Origin and fate of agricultural waste

Food and ecological footprint pyramids

Eating healthy while conserving the environment Consume ecologically friendly foods

– less meats and more plant based foods

Consume locally produced foods Minimize consumption of processed

or preserved foods Minimize waste Choose food with minimal

packaging Compost biological waste Adopt sustainable food production

methods

Let thy food be thy medicine!

Thank you!!!