Dr. Nicholas Ralston

NUTRITION AND HEALTH SESSION

CONXEMAR EXHIBITION 2021

Vigo, Spain

Problem solving for a cleaner,

greener, and healthier world.

Understanding Seafood´s Health Benefits

Studies from around the world indicate that eating seafood can help our children be smarter, and help our lives be longer and happier.

Seafoods are rich in the nutrients we need, but too many eat too little.

Seafoods are among the richest sources of healthy proteins, beneficial fats, important vitamins, and essential trace minerals.

Healthy nutrition must begin before we are born, be part of childhood, and continue throughout a hopefully long and happy life.

Healthy Hearts and Minds Require Good Nutrition

Proteins in our bodies do the work of keeping us alive. Seafoods are rich in the amino acids we need to make our proteins and enzymes.

Ocean fish are a great source of the selenium-containing amino acids that are important in the brain, heart, and endocrine tissues.

Fats provide energy and regulate protein activities. Ocean fish are rich in the omega-3 fats that make up a large fraction of the brain. These fats are also very important in controlling inflammation.

Seafoods are rich in vitamins A, B, and D as well as trace elements such as iron, zinc, iodine, magnesium, potassium, and selenium.

However, no nutrient works alone. Each must work together with other vital nutrients to enable the body’s enzymes to support health.

Seafoods are Among the Healthiest Foods on the Planet

Ocean fish contain long-chain omega-3 fats that are needed in the brain and throughout the body.

If we don’t get these long-chain omega-3 fats from our food, our body can make them, but this can be a slow process.

If a pregnant mother does not get enough long-chain omega-3 fats from her diet, her body will steal them out of her own brain to form the developing brain of her child.

This may explain why mothers that eat 2 or more ocean fish meals per week have children with IQ’s that are 7.7 points higher than children of mothers that avoid eating seafood during pregnancy.

Seafood Provides the Special Fats Your Body Needs

Ch

ild

IQ (a

ge

8)

95

100

105

110

115

n = 161

n = 893

n = 674

n = 252 n = 131

0-1 >4>1-2 >2-3 >3-4

Cord Blood Mercury Concentration (Sextiles, mg/l)

Maternal Ocean Fish Consumption Increases Child IQ

Results from the ALSPAC Study

Effects of maternal fish consumption

on IQ’s of their children)

Ocean Fish Consumption Decreases Behavior Problems

6

7

8

9

10

n = 208

0-1 >1-2 >2-3 >3-4 >4

n = 1062

n = 782

n = 272

n = 141

Beh

avio

r D

iffi

cu

ltie

s (

age

81 m

on

ths)

Cord Blood Mercury ( Sextiles, mg/l)

Results from the ALSPAC Study

Effects of maternal fish consumption

on child behavior problems (~7 years)

Seafoods are one of the few food sources of vitamin D, a fat-soluble vitamin that promotes calcium absorption and enables normal bone mineralization (important in prevention of osteoporosis) and maintains healthy metabolism throughout the body.

Because vitamin A and D are fat soluble, they are rich in fatty fish such as salmon, tuna, herring, sardines, and extracts from cod liver (a nutritional supplement that is used around the world).

Ocean fish are rich in B vitamins such as thiamin (B1), riboflavin (B2), and are good sources of vitamin B12. Because they are water soluble, the body needs a steady intake of B vitamins to make up for the amounts we lose each day.

Vitamin C and other antioxidants need selenoenzymes to restore them to their active forms that protect the brain and other tissues.

Seafoods are Vitamin Rich

Trace elements vary in soils, rivers, and lakes of various regions as well as in the foods and the fish that come from them.

Meanwhile, over the millennia the ocean has continually received the iron, zinc, iodine, magnesium, potassium, selenium, and other essential elements that are needed to support life.

This is why seafoods are among the most balanced sources of the essential elements our body needs to obtain from our diets.

Since eating ocean fish improves the health of adults and children, where did concerns about mercury, a trace element present in seafoods originate and what is currently known about this issue?

Seafoods Provide the Trace Elements We Need

Mercury was the god of speed, – and of merchants

whose commercial interests change quickly.

Mercury was also the god of thieves, and since it can

rob us of our health, mercury truly is a thief…

– but what does it steal?

Mercury, the God of Thieves

Mercury was the god of speed, – and of merchants

whose commercial interests change quickly.

Mercury was also the god of thieves, and since it can

rob us of our health, mercury truly is a thief…

– but what does it steal?

Mercury, the God of Thieves

Mercury

Sulfur

Mercury Binds with Sulfur

Mercury Sulfur Mercury Sulfide

(Cinnabar)

Binding Affinity 1039

Does mercury exposure during pregnancy harm children?

Study location Effects on Children Yes No

Minamata severe harm √

Iraq severe harm √

Effects of Maternal Mercury Exposure on Child Health

Does mercury exposure during pregnancy harm children?

Study location Effects on Children Yes No

Minamata severe harm √

Iraq severe harm √

New Zealand subtle harm √

Faroe Islands subtle harm √

Effects of Maternal Mercury Exposure on Child Health

Does mercury exposure during pregnancy harm children?

Study location Effects on Children Yes No

Minamata severe harm √

Iraq severe harm √

New Zealand subtle harm √

Faroe Islands subtle harm √

Seychelle Islands IQ benefits √

United Kingdom IQ benefits √

United States IQ benefits √

Denmark IQ benefits √

Spain IQ benefits √

Effects of Maternal Mercury Exposure on Child Health

Does mercury exposure during pregnancy harm children?

Study location Effects on Children Yes No

Minamata severe harm √

Iraq severe harm √

New Zealand subtle harm √

Faroe Islands subtle harm √

Seychelle Islands IQ benefits √

United Kingdom IQ benefits √

United States IQ benefits √

Denmark IQ benefits √

Spain IQ benefits √

Effects of Maternal Mercury Exposure on Child Health

Results of the biggest and best studies prove that mothers need to eat more fish

to improve their health and that of their children.

When selenium was discovered, it was initially mistaken for Tellurium (meaning; Earth).

When it was realized that it was a new element it was named after Selene (meaning; Moon).

Selenium is required by specialized proteins that prevent and reverse oxidative damage.

These proteins protect the brain, heart, and other tissues and we would die without them.

Only one thing can stop selenoproteins from protecting the brain from oxidative damage.

Selenium, Bright and Shiny Like the Moon

When selenium was discovered, it was initially mistaken for Tellurium (meaning; Earth).

When it was realized that it was a new element it was named after Selene (meaning; Moon).

Selenium is required by specialized proteins that prevent and reverse oxidative damage.

These proteins protect the brain, heart, and other tissues and we would die without them.

Only one thing can stop selenoproteins from protecting the brain from oxidative damage.

Mercury.

Selenium, Bright and Shiny Like the Moon

Selenium

Selenium

The concentration of selenium in the body is very low,

but it is very important in brain and endocrine tissues.

Mercury Binding to Sulfur

Mercury Mercury Selenide

Binding Affinity 1045

Selenium

Mercury prefers to bind selenium,

(a million times higher than sulfur)

Mercury can cross the placental and blood-brain barriers.

It is uniquely able to bind selenium and inhibit its activities in the brain.

Mercury and Selenium Contents of Seafoods

Selenium

Mercury

µM concentration

Cord Blood Mercury and Selenium: Faroes vs. Hawaii

y = 0.4673x + 1.3741Adjusted R² = 0.0736F= 26.55; p<0.0001

y = 9.413x + 1.7035Adjusted R² = 0.229F= 30.44 p<0.0001

0,001

0,010

0,100

1,000

10,000

0,001 0,010 0,100 1,000 10,000

Blo

od

Se

(µM

)

Blood Hg (µM)

Faroes Cord Blood

Hawaii Cord Blood

1:1 Hg:Se Molar Ratio

Seafood Selenium Health Benefit Values (HBVs)

HBV

Positive HBVSe of a seafood

indicates how beneficial it is

predicted to be.

A negative HBVSe indicates how much risk

of harm to the child that a mother eating that

seafood would be predicted to cause.

(Note: eating seafoods with positive HBV’s

diminishes risks from eating seafoods with

negative HBV’s.)

Seafood HBVs Reliably Predict Safety and Benefits

Study location Outcomes Se-HBV Yes No

Minamata Severe harm -5,000 √

Iraq Severe harm -800 √

New Zealand Subtle harm 14.4 to -123 √

Faroe Islands Subtle harm 4.0 to -83 √

Seychelles Beneficial 17.3 √

United Kingdom Beneficial 20.2 √

United States Beneficial 14.4 √

Denmark Beneficial 20.2 √

Spain Beneficial 20.2 √

Do HBV’s reliably predict the risks or benefits of eating seafoods during pregnancy?

Results of studies of maternal seafood consumption are consistent with predictions

based on the HBVs of the seafoods they were eating.

Summary

• Eating ocean fish enriches the selenium-status of mothers and their unborn children, thus protecting against mercury.

• Seafood and ocean fish consumption improve health of the hearts and minds of children and adults.

• Public health advice can no longer be based on the well intentioned, but mistaken assumptions and misunderstandings of the past.

• Since children lose nearly 8 IQ points when their mothers avoid eating ocean fish, there needs to be a concerted effort to improve seafood intakes among women and their children.

Mothers and Children Need to Eat More Seafood, Not Less

Acknowledgements:

The research described in this presentation was funded by:

U.S. Environmental Protection Agency: EPA STAR grant: G2009-STAR-B1 and

National Oceanic and Atmospheric Administration (NOAA): Grant NA09NMF4520172

and was performed in collaboration with groups of EPA and NOAA research scientists.

Seafood is Brain Food