Nuts and seeds

Types of nuts and seeds

Research shows that making nuts a regular part of a healthy diet helps to regulate our weight, and can protect against chronic diseases (such as heart disease and diabetes).

Although there has been limited research on seeds, they are thought to have similar health benefits to nuts due to their nutrient content which is comparable to nuts.

Types of nuts

Commonly eaten nuts include:

• almonds
• Brazil nuts
• cashew nuts
• hazelnuts
• macadamias
• pecans
• pine nuts
• pistachios
• walnuts
• peanuts – although actually legumes, they are classified as nuts due to their similar characteristics to other tree nuts.

Types of seeds

The nutrient profiles of seeds are also very similar to those of nuts, although they tend to have a higher proportion of polyunsaturated fats than nuts. Common seeds include:

• pumpkin seeds
• flax seeds
• sesame seeds
• poppy seeds
• sunflower seeds
• psyllium seeds
• chia seeds.

Benefits of nuts

All nuts have very similar macronutrient (protein, carbohydrate, and fat) profiles, but different types of nuts may have slightly different micronutrient (vitamin and mineral) content.

Nuts have about 29 kJ of energy per gram, and are:

• High in ‘good fats’ – monounsaturated fats (most nut types) and polyunsaturated fats (mainly walnuts).
• Low in saturated fats.
• Good sources of dietary protein – a good alternative to animal protein.
• Some nuts are also high in amino acid arginine, which keeps blood vessels healthy.
• Free of dietary cholesterol
• High in dietary fibre.
• Rich in phytochemicals that act as antioxidants.
• Rich in vitamins and minerals – vitamins include E, B6, niacin and folate and minerals include magnesium, zinc, plant iron, calcium, copper, selenium, phosphorus and potassium.

Benefits of seeds

Like nuts, most seeds are rich in:

• protein, healthy fats (higher proportion of polyunsaturated fats) and fibre
• minerals (such as magnesium, potassium, calcium, plant iron and zinc),
• vitamins B1, B2, B3 and vitamin E.

Oily seeds also contain antioxidants that stop the fats from going rancid too quickly. These antioxidants have several health benefits to the human body too.

Due to the nutrient dense characteristics of nuts and seeds, they are known to provide several health benefits, such as:

• helping to maintain your weight
• reducing your heart disease risk
• reducing your diabetes risk.

Nuts, seeds and weight management

Although nuts and seeds are high in energy and fats, eating nuts is not connected with weight gain. In fact, based on large population studies, higher nut intake has been associated with lower body weight.

When included as part of a weight-loss diet, nuts have been shown to enhance weight loss and fat loss in the abdominal region.

Lower fat in the abdominal region means lower risk for chronic diseases (such as heart disease and diabetes). Therefore, nuts should be part of a healthy diet.

The Australian Dietary Guidelines recommend 30 grams of nuts on most days of the week.

Nuts help with weight management through:

• Lower than expected fat absorption – fats in nuts are not fully digested and absorbed by the body. When less fats are absorbed it means that less energy from nuts is absorbed too.
• Hunger and fullness – nuts help to suppress our hunger. As a result, food intake is reduced to compensate for the energy from nuts. This effect is due to the protein, fat, and fibre content of nuts.

The effect of seeds on body weight has not been researched extensively but is likely to be similar to nuts as they are also high in protein, healthy fat and fibre.

Nuts, seeds and heart disease risk

Including nuts and seeds as part of your diet has been linked with a lower risk of heart disease.

Although high in fats, nuts and seeds are good sources of healthy fats (such as monounsaturated and polyunsaturated fats), and are low in (unhealthy) saturated fats.

This combination of ‘good fats’, makes nuts heart healthy – they help to reduce low density lipoprotein (LDL) cholesterol, (known as ‘bad’ cholesterol) in the body.

LDL cholesterol can add to the build-up of plaque (fatty deposits) in your arteries, which can increase your risk of coronary heart disease.

Nuts and seeds also help to maintain healthy blood vessels and blood pressure (partly through their arginine content), and reduce inflammation in the body as they are high in antioxidants.

Recommended daily serving of nuts

The Australian Dietary Guidelines recommend 30 grams of nuts on most days of the week for adults.

As all nuts have a similar nutrient content, a wide variety of nuts can be included as part of a healthy diet. One serving is approximately 30 grams – or 1/3 of a cup (or one handful). This equal to about:

• 30 almonds
• 10 Brazil nuts
• 15 cashews
• 20 hazelnuts
• 15 macadamias
• 15 pecans
• 2 tablespoons pine nuts
• 30 pistachios
• 10 whole walnuts or 20 walnut halves
• a small handful of peanuts or mixed nuts.

How to include nuts and seeds in your diet

Different types of nuts have slight differences in their vitamin and mineral content, so eating a variety of nuts will increase your levels of various nutrients.

Given that nuts and seeds have comparable nutrient composition and health benefits, consider seeds as a nut replacement in case of nut allergy (see information below).

Tips on how to make nuts and seeds a part of your diet include:

• Instead of snacking on a biscuit or piece of cake as a snack, have a handful of raw or dry roasted nuts.
• Combine nuts and seeds with low-energy dense foods (such as vegetables). This is a good way to enhance vegetable-based meals – such as in Asian-style dishes, or added to a salad.
• If you are vegan or vegetarian, nuts and seeds are a good protein substitute for meats, fish and eggs. They also contain fat, iron, zinc and niacin. You may need more than 30 grams of nuts and seeds a day to ensure adequate protein.
• There is no need to soak or remove the skin of nuts (or ‘activate’ them) unless you prefer the flavour and texture of soaked nuts. In fact, the skin of nuts is high in phytochemicals that have antioxidant and anti-inflammatory properties.
• Roasting nuts (either dry or in oil) enhances their flavour but has little impact on their fat content. This is because nuts are physically dense and cannot absorb much oil, even if they are submerged in it. Most nuts only absorb 2% of extra fats.
• Salted nuts are not recommended due to their higher sodium content – especially if you have high blood pressure. Save salted nuts for parties and make raw and unsalted roasted nuts your everyday choice.
• If you cannot tolerate the hard texture of nuts and seeds, consider eating them in unsweetened and unsalted paste forms such as nut butter and tahini (sesame paste).

Nut warnings

Be mindful of the risks when eating nuts.

Nuts can be a choking hazard

Whole nuts are not suitable for children under 3 years because they may cause choking if they are not chewed well. However, nut and seed spreads or paste (such as peanut or almond butter, or nut and seed oils) can be included in young children’s diets from 6 months.

Nuts can trigger allergic reactions

All tree nuts, peanuts and seeds may trigger life-threatening allergic reactions (anaphylaxis) in those with nut allergies.

Unlike many other allergies where children seem to ‘grow out of it’, peanut allergies tend to persist into adulthood.

There is no cure for allergies, so if you or your child have a nut or seed allergy, avoid nuts, seeds and foods containing them until you have seen a doctor who specialises in food allergies (an allergist). They will conduct medically supervised food tests to find out which nuts or seeds you may be allergic to.

Nuts and seeds should be introduced to infants and young children in the form of butters or pastes, to prevent choking. Do not give whole nuts to your child until they are 3 years.

Read food labels for traces of nuts and seeds

Always read food labels to check nuts and seeds are not present.

Beware of products that ‘may contain traces of nuts and/or seeds’. ‘Cross-contamination’ can occur during manufacturing when products without nuts and seeds are made in the same facility or on the same equipment as those containing nuts and seeds.

Where to get help

• Your GP (doctor)
• Your maternal and child health nurse
• Dietitians Australia Tel. 1800 812 942
• Allergist (a doctor who specialises in food allergies)
• Allergy & Anaphylaxis Australia. Tel. 1300 728 000