Ahimsa - Peace

In Sanskrit himsa is doing harm or causing injury. The "a" placed before the word negates it. Very simply, ahimsa is abstaining from causing hurt or harm. It is gentleness and noninjury, whether physical, mental or emotional. Look at nothing as intrinsically evil, but as sacred. We can sum this up from the Hindu, Buddhist and Jain traditions: ahimsa is higher consciousness, and himsa, hurtfulness, is lower consciousness.

Love of animals

Hinduism also promotes awareness and respect for animals. Ganesh - the deity with the head of an elephant is revered first before other deities. This reinforces respect and love for animals. Most animals are revered in one form or the other. Animals are depicted as vahanas used by the deities - starting from the lower ones like the rat and snake to bigger animals like the ox, the cow, and the elephant. Garuda - the Kite/Eagle is vahana for Vishnu and is held sacred.

Ancient Hindu religion refers to belief systems in Saptasindhu region, the site of the Indus Valley Civilization which had already flourished in that area since at least 5000 BC. Cow was recognized as a significant domestic animal. Ancient priests and philosophers also recognized the importance of the cow and elevated the cow to divine status, as Kamadhenu from the great cosmic ocean. Just like an infant breastfeeds on its mother’s milk, so do we depend heavily on the cow’s milk for our sustenance throughout our entire lives!

Love of all life

Ahimsa means nonviolence, not wishing to harm, or actually harming any being at any time. This means plants, insects, animals or humans. This means that no living entity should be injured or killed unless it is absolutely necessary. It also means that no mental misery should be inflicted on anyone. Ahimsa means that one should act in such a way that will not put others into misery or cause them confusion.
One should not destroy the trees. (Rig Veda Samhita vi-48-17)
Plants are mothers and Goddesses. (Rig Veda Samhita x-97-4)
Trees are homes and mansions. (Rig Veda Samhita x-97-5)
Sacred grass has to be protected from man's exploitation (Rig Veda Samhita vii-75-8)
Plants and waters are treasures for generations. (Rig Veda Samhita vii-70-4) Earth, atmosphere, sky, sun, moon, stars, waters, plants, trees, moving creatures, swimming creatures, creeping creatures all are hailed and offered oblations. (Taittiriya Samhita i-8-13)
One should protect the habitation. (Rig Veda Samhita vi-71-3)

Food Chain

It is also stated in scriptures, that every living entity has to live by eating another entity; that is the law of nature.
Jivo jivasya jivanan: one living entity is the life for another living entity. So violence should be committed only as much as necessary for food.
In an ecosystem, predation is a biological interaction where a predator (an organism that is hunting) feeds on its prey (the organism that is attacked and consumed). Some examples of predator and prey are cat-mouse, goat-wolf, deer-tiger, and lion-zebra.

What are the dietary restrictions of Hinduism?

There are NONE! Hinduism does not pose any restrictions on consumption of food nor drink. General guide line is to follow the path of ahimsa or non-violence, thereby not eating or limiting meat consumption. Most of the food preferance is based on local traditions, which greatly vary from place to place.
Hinduism is not about restriction, it is about inclusiveness. Supposed to unify diverse groups following varied local traditions, in to common minimum theme or program. There is no single set of rules, philosophy, tradition, but left to individuls and local groups to develop system acceptable to them.

Sattvic Tamasic Rajasic food

Food is categorized into Tamasic, Rajasic and Sattvic.
Sattvic foods are those that lead to clarity of mind and physical health. Monks avoid all spicy and smelling stuff, which are too bitter, sour, salty, pungent, dry, and hot. Some avoid garlic and onion. They feel these strong spicy foods affect meditataive practices.
Buddhist monks avoid eating strong-smelling plants, like garlic, asafoetida, shallot, mountain leek and Allium chinense. Ajvikas and Jains avoid root vegetables or underground vegetables. They eat what falls from plants or trees, to avoid giving pain to plants. Ancient Saivites from south, promoted ahimsa and vegetarianism. So, vegetarian food is called saivam food.
Tamasic foods are those that have a sedative effect on the mind and body. However, in times of pain they are allowed to alleviate suffering. Examples include: meat of an animal, fish, egg, onion, garlic, scallion, leek, chive, mushroom, and alcoholic beverages.
Rajasic foods are those that have a stimulating effect on the mind and body. They are considered to be neither beneficial nor harmful. Examples include: caffeinated drinks, paan, overly spicy salty food, and eggs.
Initially priest class (like brahmins) were meat eaters. Later changed due to Jain and saivite influence.

Vegetarianism

Vegetarianism is a natural and obvious way to live with a minimum of hurt to other beings. The opposite of causing injury to others is compassion and love for all beings. Great saints and poets like Thiruvalluvar and Rambling Daigle advocate vegetarianism. Restraint in eating and drinking is most essential for old health.

Different levels of vegeterians

Lacto-vegetarian is used to describe a type of vegetarian who eat dairy products. Many Hindu vegetarians are lacto-vegetarians who avoid eggs for religious reasons while continuing to eat dairy.
Ovo-vegetarian refers to people who do not eat meat or dairy products but do eat eggs. Milk comes from animals, usually from cows, but it is not the flesh of the animal. eggs are vegetarian, since they are not animal flesh